Knock vs OneSignal
An independent, review-free comparison compiled by the SaaSTracker editorial team. Both products are profiled in full, and neither can pay for placement here.
The short answer
Both sides assessedKnock compared with OneSignal
OneSignal is a growth team's tool with push as its deepest channel and delivery included, free for unlimited mobile push. Knock is an engineering team's tool with no delivery of its own and no marketing surface. If the question is how to reach users on their phone with a campaign, OneSignal. If the question is how to stop our product emailing people nine times an hour, Knock.
OneSignal compared with Knock
Both send notifications, but they answer to different buyers. Knock is notification infrastructure for a product engineering team, with workflows as code, bring-your-own providers, preference centers, and multi-tenancy, starting at $250 a month above a generous free tier. OneSignal is a marketing-operable engagement platform where push is the deepest channel and sending is included. Pick Knock when the notifications are part of your product; pick OneSignal when they are part of your growth loop.
Choose Knock if
Product and engineering teams at SaaS companies who need real product notifications (in-app feed, digests, preference centers, per-tenant configuration) and want the workflow logic owned by a platform a PM can edit rather than by application code an engineer has to redeploy.
Choose OneSignal if
Consumer mobile apps, marketplaces, media sites, and web publishers whose primary channel is push notifications, especially teams that want serious push infrastructure and a workable email and in-app layer for free or for tens of dollars a month rather than hundreds.
Side by side
13 attributes| Attribute | Knock | OneSignal |
|---|---|---|
| Category | Automation | Automation |
| Starting price | $0 (Developer), then $250 per month (Starter) (free plan available) | $0 (Free), then $19 per month plus usage (Growth) (free plan available) |
| Pricing model | Usage-based on messages sent, with a separate meter for Guide active users and AI agent credits, plus a large free tier and a single published paid plan before enterprise contracts. | Per-channel usage metering rather than a single contact-count meter: mobile push billed per monthly active user, web push per subscriber, email per thousand sends, with a small platform fee on Growth and quoted annual contracts above it. |
| Free plan | Developer includes 10,000 messages a month, 500 Guide active users, 500 AI agent credits, unlimited workflows, unlimited channels, unlimited team members, batching, delays, broadcasts, multi-tenancy, and Google SSO. | Unlimited mobile push sends, web push up to 10,000 subscribers per send, 10,000 email sends per month, and one active in-app message, with no expiry. |
| Free trial | No time-limited trial; the Developer plan is permanently free | No fixed trial; the permanently free plan is the evaluation path |
| Best for | Product and engineering teams at SaaS companies who need real product notifications (in-app feed, digests, preference centers, per-tenant configuration) and want the workflow logic owned by a platform a PM can edit rather than by application code an engineer has to redeploy. | Consumer mobile apps, marketplaces, media sites, and web publishers whose primary channel is push notifications, especially teams that want serious push infrastructure and a workable email and in-app layer for free or for tens of dollars a month rather than hundreds. |
| Setup time | A day to a first workflow in production for a competent backend engineer, and one to three sprints to migrate an existing homegrown notification service. The in-app feed component is typically the fastest visible win. | Under an hour for web push (a script tag) and a few hours for a mobile app, most of which is spent on APNs certificates and Firebase configuration rather than on OneSignal itself. Journeys can be running the same day. |
| Learning curve | Low for engineers, moderate for product people. The concepts (workflows, recipients, tenants, channels, preferences) are clean, but the mental model of moving decision logic out of application code into a workflow platform takes a team a couple of weeks to internalize. | Low for push and in-app, moderate for Journeys. The tag model is easy to grasp but easy to abuse, and teams who tag indiscriminately end up with segmentation logic nobody can audit six months later. Agree a tag naming convention before you start. |
| Platforms | Web dashboard, REST API, CLI, React and JavaScript components, iOS, Android, React Native, and Flutter clients, MCP server | Web app, Android SDK, iOS SDK, Flutter, React Native, Expo, Unity, Web push script, REST API |
| Compliance | SOC 2, GDPR, CCPA, HIPAA with a BAA on Enterprise | SOC 2, GDPR, CCPA |
| Founded | 2021 | 2014 |
| Headquarters | New York, New York, United States | San Mateo, California, United States |
| Ownership | Venture-backed | Venture-backed |
Strengths and limitations
Knock
Strengths
- Batching, digests, preference centers, and multi-tenancy are all first-class, and they are exactly the four things engineering teams build worst when they build them in-house.
- The free Developer tier is extraordinarily generous, including unlimited workflows, unlimited channels, unlimited team members, and multi-tenancy at $0.
- Bring-your-own-provider means you keep your sending reputation, your existing SendGrid or Twilio contracts, and your negotiated rates.
- Workflows as code with CLI, version control, CI validation, environments, and one-click rollback, which makes notification changes a normal part of the software lifecycle instead of a risk.
Limitations
- Completely unusable without engineering; there is no path where a marketer signs up and gets value, because nothing happens until code calls the API.
- The pricing cliff from $0 to $250 a month with no intermediate plan penalizes exactly the small companies the free tier attracted.
- Guides are metered separately on active users, so the in-product messaging feature has its own cost curve that is easy to miss when budgeting.
- You still pay for delivery separately, and you still own deliverability, list hygiene, and domain authentication yourself.
OneSignal
Strengths
- The best push implementation in this category by a wide margin, covering mobile, web, rich media, per-platform payload control, confirmed delivery reporting, and iOS Live Activities.
- A permanently free plan with unlimited mobile push, which removes the budget conversation entirely for early-stage consumer apps.
- Per-channel usage metering means a big dormant contact database costs nothing, the opposite of profile-based platforms where dead contacts are billable.
- First-party SDKs for Android, iOS, Flutter, React Native, Expo, and Unity that handle the permission and certificate plumbing teams usually get wrong.
Limitations
- SMS and RCS are locked behind an annual quoted Professional contract, so the cheapest self-serve path to SMS is a different vendor entirely.
- Segmentation is tag, session, and device based rather than a full behavioral event store, so sequence-dependent targeting is harder here than in Customer.io or Vero.
- No native account or company object, which makes B2B SaaS lifecycle logic awkward and rules the platform out for anyone whose messaging is organization-shaped.
- Email is a competent secondary channel, not a strong one; template tooling and list management are thinner than in email-first products.
Pricing compared
Knock
Usage-based on messages sent, with a separate meter for Guide active users and AI agent credits, plus a large free tier and a single published paid plan before enterprise contracts.
- Developer$0
- Starter$250
- EnterpriseCustom
Knock is priced as infrastructure, and the honest comparison is not against Mailchimp but against the salary cost of the engineer who would otherwise own your notification service. On that basis the free tier is remarkable value and Starter at $250 is fair, since 50,000 messages with batching, preference centers, in-app feed, and multi-tenancy is a quarter of engineering work you no longer do. The weakness is the plan gap: a team sending 15,000 messages a month is paying $250 for capability it barely uses, and the separate Guides meter means the sticker price understates the cost of using the whole product. Add your own provider bills on top and Knock is never the cheapest line on the invoice, but it is usually the one that saves the most.
OneSignal
Per-channel usage metering rather than a single contact-count meter: mobile push billed per monthly active user, web push per subscriber, email per thousand sends, with a small platform fee on Growth and quoted annual contracts above it.
- Free$0
- Growth$19
- ProfessionalCustom
- EnterpriseCustom
Judged per dollar, OneSignal is the cheapest serious multi-channel platform a small company can buy, and by some distance. Unlimited mobile push at $0 is not a loss leader trick, it is the product, and Growth at $19 plus a per-MAU rate keeps a 5,000-user app under $100 a month with email, in-app, and Journeys included. What you are not buying is a data platform: segmentation is tag and session based rather than a real behavioral event store, there is no account model, and email is a channel rather than a deliverability practice. The value is exceptional if push is your primary channel and merely fine if it is your third.
Editorial verdict on each
Knock
Knock is the right purchase when your notification problem is a product problem rather than a marketing problem. If people are complaining about email volume, if a preference center keeps slipping down the roadmap, if enterprise customers want Slack delivery, or if an engineer already owns a homegrown notification service they resent, this is the layer to buy and the free Developer tier is generous enough to prove it in a weekend. The reasons to walk away are equally clear: there is no marketing surface, nothing works without engineering, you still pay your own providers, and the leap from $0 to $250 a month with nothing in between is genuinely painful for a small team. For a five-person startup, Knock is the first thing to reach for only if you are shipping a product with an in-app notification feed. If your immediate need is onboarding emails and lifecycle campaigns, start with Customer.io, Bento, or Dittofeed and add Knock later when the product notifications become their own problem.
Read the full Knock profileOneSignal
OneSignal is the correct first choice for any small company whose primary channel is push. Nothing else in this category gives away unlimited mobile push, and nothing else handles APNs, FCM, web push, and Live Activities with this much per-platform care. Growth at $19 plus $0.012 per monthly active user keeps a real consumer app under $100 a month with Journeys, in-app messaging, and email included, and the per-channel meter means a large dormant install base costs you nothing. The limits are equally clear: segmentation is tags and sessions rather than a behavioral event store, there is no account model for B2B, email is adequate rather than good, and SMS demands an annual quoted contract. Buy it for push, keep it for in-app and email, and pair it with something else if your lifecycle logic is really about product events or company records.
Read the full OneSignal profileKnock profile last reviewed 2026-08-22; OneSignal last reviewed 2026-08-22. Pricing is compiled from public sources and can change without notice. See our methodology.