# Symbl.ai

> Symbl.ai is a conversation intelligence API platform that ingests audio, video, text, telephony, and streaming conversations and returns transcription, sentiment, entities, redaction, trackers, summaries, and a Call Score endpoint that grades a multi-party call against criteria you define, plus a Real-Time Assist API for live agent guidance; it is self-serve with a free tier of 1,000 minutes a month and pay-as-you-go pricing from $0.027 per minute, and since May 2025 it has been owned by Invoca.

- Category: Conversation Intelligence (https://saastracker.org/categories/conversation-intelligence)
- Website: https://symbl.ai
- Starting price: $0 free tier, then $0.027 per minute of audio or video pay-as-you-go
- Free plan: Up to 1,000 minutes of audio and video, 10,000 words of text, 50 Call Score criteria, and 5 minutes of Real-Time Assist per month, with up to 5 concurrent connections.
- Free trial: No fixed-length trial; the free tier serves as the evaluation path with no credit card required
- Founded: 2018, HQ: Seattle, Washington, United States, Ownership: Acquired by Invoca in May 2025
- Profile last reviewed: 2026-08-22
- Canonical profile: https://saastracker.org/products/symbl-ai

## Overview

Symbl sits one rung higher up the stack than a pure speech API, and that is the whole reason to consider it. Where AssemblyAI and Deepgram hand you a transcript and some classification, Symbl hands you conversation-native endpoints: a Call Score API that grades a call against criteria you specify, trackers that fire on phrases in real time, action item and follow-up extraction, and a Real-Time Assist API that generates a response suggestion for a frontline agent while the conversation is still happening. If you were going to build call scoring on top of a cheaper API, Symbl is the argument for not bothering.

It is still an API and not a product. There is no login for a sales manager, no call library, no coaching dashboard, no deal board, no CRM connector. The output is JSON and the buyer is a developer. What Symbl changes is the amount of that JSON you have to invent yourself, and correspondingly what it costs: $0.027 per minute for audio and video against Deepgram's fraction of a cent, and $0.10 per criteria per conversation for Call Score, which is a different pricing philosophy entirely.

The company was founded in 2018 in Seattle by Surbhi Rathore and Toshish Jawale, originally as Rammer.AI out of Techstars Seattle, and raised a $17M Series A in 2021 led by GreatPoint Ventures. In May 2025 it was acquired by Invoca, the revenue execution and call tracking company, which is the single most important fact for a small-business buyer to weigh. The self-serve free and pay-as-you-go tiers are still published and still open, but the acquirer's strategic interest is in powering Invoca's own agentic AI platform, and history in this category suggests independent developer tiers under enterprise ownership tend to get quieter over time rather than louder.

Weighed honestly: Symbl is the most capable conversation intelligence API a small team can buy self-serve, with a free tier generous enough to prototype properly at 1,000 minutes and 10,000 words a month plus 50 free Call Score criteria. It is also the one with the most acquisition risk attached, and it is meaningfully more expensive per minute than the pure speech vendors. Prototype on it, but architect so that swapping the transcription layer later is not a rewrite.

## How it works

1. You send a conversation to the platform through whichever channel it arrived on. Symbl accepts recorded audio and video files, raw text, telephony connections over PSTN, and live streaming, so a phone call, a Zoom recording, and a chat transcript can all enter the same analysis pipeline rather than needing three integrations.

2. The Understanding APIs run over the conversation and return transcription with speaker separation, sentiment measured as expressed feeling or enthusiasm, entity extraction, redaction of sensitive content, and trackers that flag whenever a phrase you care about appears. Trackers work in real time, which is what makes competitor mentions and compliance keywords actionable during the call rather than after it.

3. The Generative APIs sit on top. Summary produces the recap. Call Score is the distinctive one: you define scoring criteria and Symbl grades a multi-party call against them, returning a quality score with the reasoning, billed at $0.10 per criteria per conversation. That is a scorecard as an API call, and it is the closest thing in the API tier of this category to what a packaged coaching tool sells.

4. For live work, Real-Time Assist generates suggested responses, detects intent, and scores the call as it happens, aimed at frontline agents rather than at a manager reviewing afterwards. Compliance monitoring uses the same machinery to alert on adherence gaps in real time. Nebula, Symbl's own LLM tuned for conversational understanding, sits behind the generative endpoints and is exposed directly on enterprise agreements.

## Best for

Development teams building call scoring, agent assist, or compliance monitoring into their own software who want conversation-native endpoints rather than assembling scorecards from raw transcripts, and who can accept usage pricing and the risk profile of a recently acquired vendor.

## Not the right fit for

- Sales managers and revenue leaders; there is no interface, no library, no dashboard, and no CRM sync, so nothing here is usable without an engineer building an application first.
- Anyone optimizing for lowest cost per minute; at $0.027 per minute Symbl is roughly six times Deepgram's Nova-3 rate, and the Call Score per-criteria charge compounds on high-volume analysis.
- Buyers who need certainty that the self-serve tier will still exist in three years, since Invoca acquired Symbl in May 2025 and its strategic priority is its own platform rather than an independent developer business.
- Teams needing deal boards, pipeline forecasting, or CRM field write-back, none of which exist at any tier because this is infrastructure and not a revenue product.
- Small businesses without engineering capacity, for whom the free tier is a trap: it costs nothing and delivers nothing without code.

## Features

### Conversation ingestion

More input channels than any other API on this list, which is the practical differentiator.

- **Audio and video file processing**: Recorded meetings and calls are submitted as files or URLs and analysed asynchronously, billed per minute of media.
- **Telephony over PSTN**: Symbl can join a phone call directly rather than requiring you to capture and upload the audio yourself, which is unusual among conversation APIs and matters for inside-sales and contact-centre work.
- **Live streaming connections**: A streaming interface for real-time analysis, which is what the Real-Time Assist and live tracker features depend on.
- **Text and chat conversations**: Chat transcripts and messaging threads run through the same understanding models as voice, billed per word rather than per minute, so support conversations across channels get analysed consistently.
- **Concurrency limits by tier**: Up to 5 concurrent connections on the free tier and up to 50 on pay-as-you-go, which is the practical gate between prototype and production.

### Understanding APIs

The classification layer, comparable to what AssemblyAI and Deepgram offer.

- **Transcription with speaker separation**: Multi-party transcription with speaker attribution, the prerequisite for talk ratio and any per-person coaching metric you build.
- **Sentiment analysis**: Measures a speaker's expressed feeling or enthusiasm rather than a flat positive or negative label, which is a more useful signal for reading how a call is going.
- **Trackers**: Watch for defined phrases and concepts and fire when they appear, in real time. This is the primitive behind competitor tracking, objection detection, and compliance keyword alerting.
- **Entity extraction**: Names, organizations, amounts, and dates pulled from the conversation as structured fields rather than as text you have to parse.
- **Redaction**: Sensitive information removed from the conversation output, the control that lets you store call data from regulated interactions.
- **Topics and action items**: Automatic segmentation into topics and extraction of commitments and follow-ups, which is the difference between a transcript and a usable record of what a call decided.

### Generative APIs and Call Score

The layer that separates Symbl from a pure speech vendor.

- **Call Score API**: Grades a multi-party call against criteria you define and returns a quality score with reasoning, billed at $0.10 per criteria per conversation with the first 50 criteria free.
- **Custom scoring criteria**: Because criteria are yours rather than a fixed rubric, a MEDDICC scorecard, a compliance checklist, or a support quality form can all be expressed without a feature request to a vendor.
- **Summary API**: Conversation summarization as a dedicated endpoint rather than as a prompt you write and maintain.
- **Nebula LLM**: Symbl's own language model tuned for understanding and generating human conversation, sitting behind the generative endpoints and exposed directly on enterprise agreements.
- **Nebula embeddings**: Conversation-tuned embeddings for search and clustering across a call archive, useful for building semantic search over your own recordings.

### Real-time assist and compliance

The live layer, aimed at frontline agents rather than at post-call review.

- **Real-Time Assist API**: Generates suggested responses and detects intent during a live conversation, so a support or sales agent gets help while the customer is still on the line. Free tier includes 5 minutes.
- **Live call scoring**: Scoring applied during the conversation rather than after it, which is what makes intervention possible rather than just review.
- **Compliance monitoring**: Real-time alerts when adherence to a compliance policy slips, built on the tracker machinery, aimed at regulated contact-centre work.
- **Intent detection**: Identification of what the customer is trying to accomplish, which is more useful in support routing and voice agents than in sales coaching.
- **Voice agent building blocks**: The same primitives support automated agents that understand and respond, which is the direction the Invoca acquisition pushed the roadmap.

## Use cases

- **Product team adding call QA to a support platform**: Customers want every support call scored against their own quality form, and building a scoring model from raw transcripts is months of work with uncertain accuracy. Outcome: Call Score takes the customer's criteria directly and returns a graded result per call at $0.10 per criteria, so the feature ships in weeks with the rubric configurable per customer.
- **Contact centre building live agent assist**: New agents need the right answer while the customer is talking, and hiring enough supervisors to whisper guidance does not scale. Outcome: Real-Time Assist detects intent and generates suggested responses in the stream, and trackers fire compliance alerts before a policy gap becomes a regulatory problem.
- **Vertical SaaS company embedding conversation analysis**: Customers in a specific industry want their calls analysed inside the existing product, and sending them to a separate conversation intelligence vendor is not acceptable. Outcome: Telephony ingestion, trackers, and Call Score are wired into the product directly, so the analysis appears as a native feature and the vendor relationship stays invisible to the end customer.
- **Team prototyping before committing to a build**: Nobody knows yet whether automated call scoring will actually be accurate enough to be worth building a product around. Outcome: The free tier's 1,000 minutes, 10,000 words, and 50 Call Score criteria a month is enough to test the hypothesis honestly before any money or architecture is committed.

## Pricing

Usage-based with a free tier and self-serve pay-as-you-go, metered per minute for audio and video, per word for text, and per criteria per conversation for Call Score. Enterprise agreements add volume discounts, higher concurrency, and direct Nebula model access.

- **Free**: $0 per month. 1,000 minutes of audio and video; 10,000 words of text; 50 Call Score criteria; 5 minutes of Real-Time Assist; Up to 5 concurrent connections. Generous enough to build and test a real prototype, which is rare among conversation APIs.
- **Pay-as-you-go**: $0.027 per minute of audio or video. First 1,000 minutes free, then $0.027 per minute to 30,000; $0.017 per minute above 30,000 minutes; Text at $0.0002 per word, dropping to $0.00012 above 3.75M words; Call Score at $0.10 per criteria per conversation; Up to 50 concurrent connections.
- **Enterprise**: Custom quoted. Volume discounts below published rates; Higher concurrency limits; Direct Nebula Model API access; Contractual support and compliance arrangements.

Billing notes:

- Audio and video pricing steps down with volume: free to 1,000 minutes, $0.027 to 30,000, then $0.017 above that, so unit economics improve materially at scale.
- Call Score is billed per criteria per conversation, so a ten-point scorecard costs $1.00 per call, which is a very different cost curve from per-minute transcription and needs modelling before you design the rubric.
- Text is billed per word rather than per minute, which makes chat and messaging analysis cheap relative to voice.
- There is no seat concept, so the per-recorded-user versus per-team-member question that dominates the rest of this category does not apply.
- At $0.027 per minute Symbl is roughly six times Deepgram's Nova-3 rate for transcription alone; you are paying for the higher-level endpoints, not for the words.
- Invoca acquired Symbl in May 2025, so treat the published self-serve pricing as current rather than guaranteed, and avoid architecting a business around it without a fallback.

Value assessment: Symbl is expensive per minute and cheap per unit of engineering. If your build needs call scoring, real-time assist, and trackers, buying them as endpoints costs far less than the months it takes to build equivalents on a raw speech API, and the free tier lets you prove that before paying. If all you need is transcription, you are overpaying by a factor of six against Deepgram for capabilities you will not use. The Call Score per-criteria model rewards tight scorecards and punishes sprawling ones, so design the rubric with the bill in mind. The largest uncosted risk is ownership: Invoca bought this to power its own platform, and the self-serve tier is not the acquirer's strategic priority.

## Strengths

- Conversation-native endpoints rather than raw primitives: Call Score, trackers, action items, and Real-Time Assist are things you would otherwise spend months building on a speech API.
- The widest ingestion surface on this list, covering audio, video, text, telephony over PSTN, and streaming, so channels do not each need their own integration.
- A genuinely usable free tier at 1,000 minutes, 10,000 words, 50 Call Score criteria, and 5 minutes of Real-Time Assist per month, which is enough to prototype honestly.
- Call Score criteria are yours to define, so any scoring rubric can be expressed without waiting for a vendor to build it as a feature.
- Nebula, an in-house LLM tuned for conversational understanding, plus conversation-tuned embeddings for semantic search over a call archive.
- Real-time trackers and compliance alerting are production-grade capabilities aimed at contact centres, not demo features.

## Limitations

- Owned by Invoca since May 2025, which makes the long-term future of an independent self-serve developer tier genuinely uncertain and is the main reason to hedge your architecture.
- Roughly six times the per-minute transcription cost of Deepgram, which is only justified if you use the higher-level endpoints.
- Call Score at $0.10 per criteria per conversation scales badly with detailed rubrics; a twelve-point scorecard across a thousand calls a month is $1,200.
- No interface of any kind: no library, no dashboard, no scorecard UI, no CRM integration, and nothing a non-engineer can use.
- Nothing addresses recording consent, disclosure, or two-party consent law; those obligations belong entirely to your application, and the telephony ingestion path makes them more acute rather than less.
- Public documentation and community activity are thinner than AssemblyAI's or Deepgram's, and post-acquisition the developer relations investment is unlikely to grow.

## Comparisons

- **Symbl.ai vs AssemblyAI**: AssemblyAI is cheaper, better documented, independently owned, and supplies an LLM Gateway so you can build scoring with your own prompts. Symbl gives you Call Score and Real-Time Assist as finished endpoints plus telephony ingestion. Choose AssemblyAI for cost, stability, and control; choose Symbl when the higher-level endpoints save you enough engineering to justify the price and the ownership risk.
- **Symbl.ai vs Deepgram**: Deepgram is roughly six times cheaper per minute, faster, self-hostable, and backed by a $1.3B valuation and a fresh $130M round. Symbl is far higher up the stack, with scoring, trackers, and live assist supplied. If your problem is transcription volume, Deepgram wins outright; if your problem is that you do not want to build a scorer, Symbl earns its premium.
- **Symbl.ai vs Grain**: Grain is the packaged version of what Symbl lets you build: recording, a shared library, coaching, and CRM sync for around $29 a seat with free viewer licenses and no code. Symbl is the API a company would use to build a competing product. For a sales team, Grain wins without argument; for a software company shipping conversation features, only Symbl makes sense.
- **Symbl.ai vs Avoma**: Avoma delivers methodology scorecards, semantic trackers, dialer capture, and deal risk as a finished platform from $19 a seat plus $29 modules. Symbl delivers scoring and live assist as endpoints at usage prices with nothing built around them. Buy Avoma if you have reps to coach; license Symbl if you have customers to sell software to.
- **Symbl.ai vs CallRail**: CallRail and Symbl now sit oddly close together, since Invoca owns Symbl and competes directly with CallRail in call tracking and conversation intelligence. CallRail is the finished self-serve product for a services business at $150 to $195 a month; Symbl is the API layer, priced per minute, that a competitor would build on. Small businesses buy CallRail; developers license Symbl.

## Implementation

- Setup time: An hour to a first analysed conversation using the free tier and the documented endpoints. Considerably longer to production, because storage, playback, reporting, and any interface are yours to build.
- Learning curve: Moderate for a developer. The API surface is broader than a pure speech vendor's, so there is more to learn, but the higher-level endpoints mean less to invent. Not applicable to non-technical users.
- Onboarding: Fully self-serve for the free and pay-as-you-go tiers with no sales contact required. Enterprise agreements and direct Nebula access involve Invoca's team.
- Migration: Given the acquisition, architect for portability: keep transcription behind an interface so a swap to Deepgram or AssemblyAI is a configuration change rather than a rewrite, and store the raw analysis output in your own database rather than relying on the vendor to retain it. Historical audio can be reprocessed in bulk at published per-minute rates.

## Platform, API & security

- Platforms: REST API, Streaming API, Telephony over PSTN, Text and chat ingestion, Client SDKs
- API: The product is the API: Understanding APIs for transcription, sentiment, entities, redaction, trackers, topics, and action items; Generative APIs for Call Score and Summary; Real-Time Assist for live guidance; and Nebula LLM and embeddings on enterprise agreements.
- Compliance: SOC 2, GDPR, Redaction primitives for sensitive data handling
- Data residency: Not published as a self-serve selectable option; enterprise arrangements are handled through Invoca.
- SSO: API key authentication for self-serve accounts; identity integration is an enterprise agreement concern.
- Security notes: Redaction is available as a first-class Understanding API for stripping sensitive content, and compliance monitoring can alert in real time on policy adherence gaps. Recording consent, disclosure, and two-party consent obligations belong entirely to the application built on top, and the PSTN telephony ingestion path makes those obligations more immediate since Symbl can be on the call itself.

## Support

- Channels: Email and developer support, Enterprise support through Invoca agreements
- Documentation: Developer documentation at symbl.ai covering the Understanding, Generative, Real-Time Assist, and Nebula APIs, with quickstarts and SDK references.
- Community: A developer blog and community presence that was more active before the acquisition; smaller than AssemblyAI's or Deepgram's ecosystems.

## Company

- Founded: 2018
- Founders: Surbhi Rathore, Toshish Jawale
- Headquarters: Seattle, Washington, United States
- Ownership: Acquired by Invoca in May 2025
- Employees: Not separately disclosed since the Invoca acquisition
- Funding: Raised approximately $17M in a 2021 Series A led by GreatPoint Ventures, with Gutbrain Ventures, PBJ Capital, Crosscut Ventures, Flying Fish, Jump Capital, Third Kind VC, and Technexus Ventures participating, before being acquired by Invoca in May 2025 for an undisclosed amount.

Funding history:

- Techstars and seed (2019): Not disclosed. Graduated Techstars Seattle under the name Rammer.AI before rebranding to Symbl.
- Series A (2021): $17M. Led by GreatPoint Ventures with Crosscut, Flying Fish, Jump Capital, and others participating.
- Acquisition (2025): Undisclosed. Acquired by Invoca in May 2025 to power agentic AI across digital, voice, and messaging channels.

Timeline:

- 2018: Founded in Seattle by Surbhi Rathore and Toshish Jawale as Rammer.AI, building conversation understanding as a developer API.
- 2019: Graduates Techstars Seattle and rebrands to Symbl.ai.
- 2021: Raises a $17M Series A led by GreatPoint Ventures and expands from transcription analysis into trackers and action item extraction.
- 2023: Launches Nebula, an in-house LLM tuned for understanding and generating human conversation, alongside conversation embeddings.
- 2024: Ships the Call Score API for grading multi-party calls against custom criteria and the Real-Time Assist API for live frontline guidance.
- 2025: Acquired by Invoca in May, with the platform positioned to power agentic AI across Invoca's digital, voice, and messaging channels while the self-serve tiers remain published.

## Integrations

REST API for recorded audio and video, Streaming API for real-time conversations, Telephony over PSTN, Text and chat conversation ingestion, Nebula LLM and embeddings on enterprise agreements, Invoca platform following the 2025 acquisition, No native CRM, meeting platform, or dashboard integrations of its own

## FAQ

### What is Symbl.ai?

Symbl.ai is a conversation intelligence API platform. It ingests audio, video, text, telephony, and streaming conversations and returns transcription, sentiment, entities, redaction, trackers, topics, and action items, plus a Call Score endpoint that grades a call against criteria you define and a Real-Time Assist API for live agent guidance. It is infrastructure for developers, not an application.

### Does Symbl give me a dashboard or record my sales calls?

No. There is no recording bot for meetings, no call library, no manager dashboard, no scorecard interface, no deal board, and no CRM integration. It returns JSON. A sales manager cannot use Symbl without an engineer building an application on top of it first.

### How much does Symbl.ai cost?

The free tier covers 1,000 minutes of audio or video, 10,000 words of text, 50 Call Score criteria, and 5 minutes of Real-Time Assist per month. Pay-as-you-go is $0.027 per minute to 30,000 minutes and $0.017 above that, text is $0.0002 per word, and Call Score is $0.10 per criteria per conversation. Enterprise pricing is custom.

### What is the Call Score API and how is it billed?

It grades a multi-party call against criteria you define, returning a quality score with reasoning. Billing is $0.10 per criteria per conversation, with the first 50 criteria free each month. That means a ten-point scorecard costs a dollar per call, so a detailed rubric across high call volume gets expensive quickly and the rubric should be designed with the bill in mind.

### Who owns Symbl.ai now?

Invoca, the revenue execution and call tracking company, acquired Symbl in May 2025 for an undisclosed amount. The self-serve free and pay-as-you-go tiers remain published, but the acquirer's strategic interest is in powering its own agentic AI platform, so treat the independent developer offering as current rather than guaranteed and keep your architecture portable.

### How does Symbl compare with AssemblyAI and Deepgram on price?

It is substantially more expensive per minute: $0.027 against roughly $0.0043 for Deepgram's Nova-3 and $0.15 per hour for AssemblyAI's Universal-2. You are not paying for better transcription, you are paying for the higher-level endpoints such as Call Score and Real-Time Assist. If you only need a transcript, the other two are far better value.

### Can Symbl join a phone call directly?

Yes. Telephony ingestion over PSTN is supported, which is unusual among conversation APIs and useful for inside-sales and contact-centre work where the audio is on a phone line rather than in a video meeting. It also raises the consent question sharply, since Symbl is on the call rather than processing a file you already captured.

### How does Symbl handle recording consent and two-party consent law?

It does not, by design. Consent, disclosure, and jurisdictional compliance are obligations of the application you build, which is especially important on the PSTN path where Symbl participates in the live call. What Symbl provides is a first-class Redaction API for stripping sensitive information and compliance monitoring that alerts in real time when policy adherence slips.

### Is there a per-seat price?

No. There are no seats. Pricing is per minute of media, per word of text, and per criteria per conversation, so the question of whether you pay per recorded user or per team member does not apply. Any number of people can view whatever your application shows them without affecting the bill.

### What is Nebula?

Nebula is Symbl's own large language model, tuned specifically for understanding and generating human conversation, along with a matching embeddings model for semantic search across a call archive. It sits behind the generative endpoints such as Call Score and Summary, and direct API access to it is an enterprise-tier arrangement.

### Should a small business build on Symbl today?

Only with a hedge. The free tier is generous enough to prototype properly and the conversation-native endpoints save real engineering, so it is a good place to test whether automated call scoring works for your use case. But given the Invoca acquisition, keep transcription behind an abstraction and store analysis results in your own database so that a move to AssemblyAI or Deepgram later is a configuration change rather than a rebuild.

## Editorial verdict

Symbl is the most capable conversation intelligence API a small team can still sign up for without a sales call, and Call Score plus Real-Time Assist genuinely remove months of work for anyone building scoring or agent assist into their own software. The free tier is generous, the ingestion surface including PSTN telephony is the widest here, and the trackers and compliance alerting are production features rather than demos. Two things should temper enthusiasm: it costs roughly six times Deepgram per minute for transcription you may not need at that quality, and Invoca has owned it since May 2025, which makes the independent self-serve tier a strategic afterthought rather than a strategic priority. Prototype on it, price the Call Score rubric carefully, and architect so that swapping the layer underneath is never a rewrite. And if you are a sales manager rather than a developer, this is not your product at all.

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Source: SaaSTracker (https://saastracker.org), an independent editorial project. This profile is compiled from public information, carries no peer reviews or paid placement, and was last reviewed 2026-08-22. Awards are judged on published criteria: https://saastracker.org/methodology