Mail-Tester vs Unspam
An independent, review-free comparison compiled by the SaaSTracker editorial team. Both products are profiled in full, and neither can pay for placement here.
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The short answer
Both sides assessedMail-Tester compared with Unspam
Both are cheap pre-send checkers with real free tiers, and they overlap less than they look. Unspam bundles spam testing with inbox placement, rendering previews across 50-plus clients, screenshots, and heatmaps, giving 21 tests a month free and pay-per-test above that. Mail-Tester does one thing, scores a message with SpamAssassin, and does it three times a day for free with a much cleaner API story. Choose Unspam when design rendering and placement matter alongside the score; choose Mail-Tester when the score is the whole requirement or you need to embed it.
Unspam compared with Mail-Tester
Both are cheap pre-send checkers with real free tiers and they overlap less than the category page suggests. Unspam covers spam scoring plus inbox placement, rendering across 50-plus clients, screenshots, and heatmaps, giving 21 tests a month free and pay-per-test above. Mail-Tester does one job, a SpamAssassin score out of ten, three times a day free, with a much stronger API and white-label story. If broken dark-mode layouts and placement matter alongside the score, Unspam. If the score is the requirement, or you are embedding it, Mail-Tester.
Choose Mail-Tester if
Anyone who needs a fast, credible answer to whether a specific message is technically clean before sending it, and developers who want that answer inside their own product through an API or an embedded, white-labelled result page.
Choose Unspam if
Small marketing teams, agencies, and solo senders who need pre-send spam scoring, provider-by-provider placement evidence, and cross-client rendering checks in one cheap subscription rather than paying separately for a deliverability tool and a rendering tool.
Side by side
13 attributes| Attribute | Mail-Tester | Unspam |
|---|---|---|
| Category | Deliverability | Deliverability |
| Starting price | $0 (3 tests per 24 hours), then $10 per month for 50 tests | $0 (Free, 21 tests a month), then pay per test on Custom |
| Pricing model | Free for three tests every 24 hours with no account. Paid subscriptions are priced by monthly test volume, with one-time payment options alongside, and the per-test rate falls as volume rises. Quotas reset monthly and do not roll over. | Two free tiers plus a single paid Custom plan billed per test, at rates that fall with volume. The fixed Basic, Business, and Agency subscriptions were retired in 2026 and replaced by the pay-per-test model. |
| Free plan | Three tests in any rolling 24 hours with no account and no card, results kept for seven days, plus free SPF, DKIM, DMARC, and BIMI lookup tools. | Free gives 21 tests a month: 5 spam tests, 3 inbox placements, 3 device previews, 5 email screenshots, and 5 heatmaps, with results kept 14 days. A no-account tier runs a smaller allowance straight from the page with results kept 24 hours. |
| Free trial | No separate trial; the free three tests a day serve as the evaluation path and do not expire | No separate trial; two free tiers serve as the evaluation path, one of them requiring no signup at all |
| Best for | Anyone who needs a fast, credible answer to whether a specific message is technically clean before sending it, and developers who want that answer inside their own product through an API or an embedded, white-labelled result page. | Small marketing teams, agencies, and solo senders who need pre-send spam scoring, provider-by-provider placement evidence, and cross-client rendering checks in one cheap subscription rather than paying separately for a deliverability tool and a rendering tool. |
| Setup time | Under a minute for the free test, with nothing to install or connect. An API or white-label integration is a few hours of developer time. | Under ten minutes. Create an account, send a test message to the address provided, and read the result. There is no DNS change, no mailbox connection, and no configuration. |
| Learning curve | Very low to run, moderate to interpret. The report itemises deductions clearly, but knowing which of them genuinely matter, and which are SpamAssassin being pedantic about a template, takes a little experience. | Low. The spam score is itemized in plain language and the rendering previews are self-explanatory. The one thing a buyer must understand is what a seed test does and does not prove, and that is a conceptual point rather than a product one. |
| Platforms | Web application, JSON API, iframe embed | Web application, Seed list testing from any sending platform |
| Compliance | None published | GDPR |
| Founded | 2014 | 2021 |
| Headquarters | France | Not publicly disclosed |
| Ownership | Privately held; the operating company is not named publicly | Privately held, independent |
Strengths and limitations
Mail-Tester
Strengths
- Three genuinely free tests every 24 hours with no account, which is the lowest-friction real answer available anywhere in this category.
- Built on SpamAssassin, so deductions name a specific rule rather than an opaque proprietary score.
- Tests your actual sending path, because you send from the system you will really use rather than through a relay.
- Covers authentication, blacklists, links, HTML, and server configuration in one report rather than across four tools.
Limitations
- It scores a message against a filter; it does not test inbox placement at Gmail, Outlook, and Yahoo the way GlockApps, Unspam, or a seed-list product does.
- No monitoring of any kind. It answers when asked and watches nothing in between, so reputation drift is invisible to it.
- No warming, no sending, and no reputation management, so it is always one tool in a stack rather than the stack.
- The operators publish almost nothing about themselves: no company name, no founders, no location beyond being French, and no compliance documentation.
Unspam
Strengths
- Bundles spam scoring, inbox placement testing, and cross-client rendering in one cheap subscription, replacing two separate tools for most small teams.
- A free tier that is genuinely usable, with three placement tests and ten spam tests a month and no credit card required.
- Unlimited sender accounts on every tier including free, so agencies do not pay per client domain.
- Light and dark mode rendering across more than fifty real clients and devices, which catches the failures that dark mode introduces and nobody sees by eye.
Limitations
- Seed testing measures a panel of test inboxes, not your actual recipients; personalized engagement history means a clean seed result and a spam-foldered campaign can coexist, and this is true of every placement tester, not just this one.
- Seed panel size and provider composition are less thoroughly documented than GlockApps publishes, so it is harder to judge how representative a result is.
- No continuous monitoring; testing is on-demand at the moment you send, so a reputation problem developing between campaigns goes unseen.
- No DMARC aggregate report ingestion, so it cannot tell you who else is sending as your domain or drive you to a p=reject policy.
Pricing compared
Mail-Tester
Free for three tests every 24 hours with no account. Paid subscriptions are priced by monthly test volume, with one-time payment options alongside, and the per-test rate falls as volume rises. Quotas reset monthly and do not roll over.
- Free$0
- 50 tests a month$10
- 500 tests a month$25
- 2,000 tests a month$80
- 7,500 tests a month$250
Judged as a free tool, Mail-Tester is the best value in this category and it is not close: three real tests a day, built on SpamAssassin, with no account, covers the entire pre-send checking need of a small sender at no cost. Judged as a paid product it is narrow but priced honestly, and the buyers who get the most from it are not individuals at all but products embedding the report through the API and white-label. What it does not do should decide the purchase: no placement testing at named providers, no monitoring, no warming. If the question is whether this specific message is technically clean, nothing is faster or cheaper. If the question is where your mail is landing at Gmail this week, you need GlockApps, Unspam, or a warming platform with testing built in.
Unspam
Two free tiers plus a single paid Custom plan billed per test, at rates that fall with volume. The fixed Basic, Business, and Agency subscriptions were retired in 2026 and replaced by the pay-per-test model.
- No account$0
- Free$0
- CustomPay per test
On price, Unspam is not really competing with the dedicated placement platforms; it undercuts them heavily and folds in rendering testing that would otherwise be a separate Litmus or Email on Acid subscription. The move to pay-per-test makes the paid end harder to judge from outside, because no starting rate is published, but it also means a team that only wants placement tests stops subsidising the rendering features it never opens. The free end is where the value is now unambiguous: 21 tests a month at no cost, and a smaller allowance with no account at all. What you are buying either way is a competent generalist rather than the deepest instrument in any one dimension. GlockApps has a larger, better-documented seed panel and continuous monitoring; Litmus has more rendering depth. For a small business that needs both jobs done adequately, Unspam is the obvious purchase, and the free tier means the decision costs nothing to test.
Editorial verdict on each
Mail-Tester
Mail-Tester earns its place in any deliverability stack by being free, fast, and specific. Three tests a day with no account, a score out of ten backed by SpamAssassin, and a report that names the exact rule costing you points is the cheapest useful thing a sender can do before launching a campaign, and the paid tiers are honestly priced for the agencies and products that run it at volume. The API, white-labelling, and micro-payment resale explain why the tool turns up inside other vendors' products, and make it a genuine build-versus-buy answer for anyone adding deliverability checks to their own software. Understand the boundary before relying on it: this is a technical cleanliness check, not a placement test and not a monitor. A ten out of ten tells you nothing about which Gmail tab you landed in, and nothing at all about next week. Use it constantly, for free, alongside a warming and monitoring platform that covers what it deliberately does not.
Read the full Mail-Tester profileUnspam
Ease of UseUnspam is the cheapest sensible way for a small business to answer two questions at once: is this message likely to be filtered, and does it look right on the devices people will read it on. Bundling placement testing with fifty-plus client renders in light and dark mode undercuts the combination of a deliverability tool and a rendering tool by a wide margin, unlimited sender accounts make it unusually agency-friendly, and the free tier is a real plan rather than a teaser. It is not the deepest instrument in either dimension: GlockApps documents a better seed panel and monitors continuously, and Litmus renders more thoroughly. And like every placement tester, it measures a panel of seed inboxes rather than your actual recipients, so a clean result is reassurance and not proof. Buy it for pre-send QA on a budget. Do not buy it expecting it to fix a reputation problem, because measuring is all it does.
Read the full Unspam profileMail-Tester profile last reviewed 2026-09-20; Unspam last reviewed 2026-09-20. Pricing is compiled from public sources and can change without notice. See our methodology.
The best in Email Deliverability & Warming
23 trackedEmail deliverability and warming tools build and protect sender reputation by exchanging positive engagement signals between real inboxes, and by monitoring where a sender's mail actually lands.
The most complete pairing of warming network quality with actionable spam-placement testing in the category.
A free tier with real test credits and a $59 entry point put audit-grade placement, DMARC, and blacklist visibility within any sender's budget.
Founded in 2024, InboxDoctor undercuts the entire warming market at $2 per mailbox with Google Postmaster integration included on every tier.
Rethought warming twice in one product: an AI Persona behind every mailbox in place of detectable network patterns, and a seedlist of thousands of trusted inboxes that campaigns are pre-sent to at scale for delivery feedback and engagement before launch.
A placement and spam test takes under ten minutes with no DNS change or mailbox connection, and the itemized score explains every fix in plain language.
Frequently asked questions
6 questionsWhat is the difference between Mail-Tester and Unspam?
Both are cheap pre-send checkers with real free tiers, and they overlap less than they look. Unspam bundles spam testing with inbox placement, rendering previews across 50-plus clients, screenshots, and heatmaps, giving 21 tests a month free and pay-per-test above that. Mail-Tester does one thing, scores a message with SpamAssassin, and does it three times a day for free with a much cleaner API story. Choose Unspam when design rendering and placement matter alongside the score; choose Mail-Tester when the score is the whole requirement or you need to embed it.
Is Mail-Tester or Unspam cheaper?
Mail-Tester starts at $0 (3 tests per 24 hours), then $10 per month for 50 tests. Unspam starts at $0 (Free, 21 tests a month), then pay per test on Custom. The billing models differ, so the entry price is rarely the whole cost. Mail-Tester pricing model: Free for three tests every 24 hours with no account. Paid subscriptions are priced by monthly test volume, with one-time payment options alongside, and the per-test rate falls as volume rises. Quotas reset monthly and do not roll over. Unspam pricing model: Two free tiers plus a single paid Custom plan billed per test, at rates that fall with volume. The fixed Basic, Business, and Agency subscriptions were retired in 2026 and replaced by the pay-per-test model.
Does Mail-Tester or Unspam have a free plan?
Mail-Tester has a free plan. Three tests in any rolling 24 hours with no account and no card, results kept for seven days, plus free SPF, DKIM, DMARC, and BIMI lookup tools. Trial terms: No separate trial; the free three tests a day serve as the evaluation path and do not expire. Unspam has a free plan. Free gives 21 tests a month: 5 spam tests, 3 inbox placements, 3 device previews, 5 email screenshots, and 5 heatmaps, with results kept 14 days. A no-account tier runs a smaller allowance straight from the page with results kept 24 hours. Trial terms: No separate trial; two free tiers serve as the evaluation path, one of them requiring no signup at all.
Who should choose Mail-Tester?
Anyone who needs a fast, credible answer to whether a specific message is technically clean before sending it, and developers who want that answer inside their own product through an API or an embedded, white-labelled result page.
Who should choose Unspam?
Small marketing teams, agencies, and solo senders who need pre-send spam scoring, provider-by-provider placement evidence, and cross-client rendering checks in one cheap subscription rather than paying separately for a deliverability tool and a rendering tool.
What are the best alternatives to Mail-Tester and Unspam?
SaaSTracker profiles 23 products in Email Deliverability & Warming. The Summer 2026 awards in the category went to MailReach (Category Leader), GlockApps (Best Value), InboxDoctor (Momentum). Every profile is compiled from primary sources, so a shortlist can be built from pricing, limitations, and fit rather than from star ratings.
