Email on Acid pricing and review

Reachkit, the company behind this page, sells a cold email platform and shows up below as one alternative. The prices here come from emailonacid.com and mailgun.com, both checked in October 2026.

Email on Acid pricing now means Mailgun Inspect: $99 a month for 1,000 previews or $199 for 2,000. Both the emailonacid.com pricing page and Mailgun’s Inspect page list the same three plans, monthly only, as of October 2026.

Every plan has unlimited users. Past the allowance, Basic and Premium bill $0.15 per preview, and Mailgun says it pauses usage before a big bill, though some overage can still accrue. Both plans start with a free month.

How previews count: one screenshot of one client or device is one preview, so a test across 50 clients uses 50. A full run on about 100 clients gives you roughly 10 tests a month on Basic and 20 on Premium. On Basic, 1,500 previews cost $174, and past about 1,667 a month Premium is the cheaper plan. Link, accessibility and spam checks don’t use previews.

The old plans: Email on Acid used to sell per-user plans with unlimited previews, such as The Basics at $99 a month for one user (Software Advice). A Reddit user called the switch “a jump from $74 to $99, up 33%”, which matches the old yearly rate on third-party price lists; on monthly billing the entry price stayed at $99, now with unlimited seats. The old sign-up form is still live with a 7-day trial, but shows no price. Current subscribers get a migration discount of unpublished size.

Email on Acid is a quality check for emails you build and send somewhere else. It doesn’t send anything itself, and Mailgun says Inspect “can be used with any email service provider” (launch post).

You get an email in by sending it from your email platform to a test address or by pasting the HTML. Each test shows it in 100+ clients and devices, including mobile and dark mode, and flags broken links, missing images, unsupported code and accessibility problems against WCAG 2.2, the web accessibility standard. The spam check reviews content against major mailbox providers, split into B2B and B2C. It isn’t a seed-based inbox placement test; Mailgun sells those separately in Optimize.

Mailgun calls Inspect “a complete rebuild” on its own platform and announced it as Email on Acid’s successor in April 2026, with customers set to start moving over in June 2026. New in 2026: Gmail on iOS previews, Chrome and VS Code extensions and an HTML editor (release notes). AI suggestions are on the roadmap, not shipped.

Strengths

• A price you can see. $99 a month buys a self-serve plan, while Litmus now quotes through sales.
• Quick to use. G2’s review summary says users “consistently praise the ease of use and speed of rendering”, and the homepage says results arrive in under 10 seconds.
• Coverage plus accessibility. 100+ clients and devices and WCAG 2.2 checks sit in one test.
• No seat math. Every Inspect plan comes with unlimited users and API access, which helps agencies with many reviewers.

Drawbacks

• Previews are metered. Email on Acid’s own 2024 post said “unlimited testing with every paid plan”; Inspect caps previews at 1,000 or 2,000 a month.
• The extra checks need Premium. Accessibility, code, link and spam checks come with the $199 plan. Basic is previews and the API.
• History stays behind. Mailgun says past tests and previews won’t move to Inspect.
• Trial billing. Two Trustpilot reviewers in 2022 say they were charged $179 when a free trial ended. Email on Acid’s refund help article says monthly subscriptions get no refunds.

Email on Acid holds 4.5 out of 5 on G2 from 43 reviews, 4.4 on Capterra from about 30 and 4.9 on Gartner Peer Insights from 9, per search listings in October 2026. Trustpilot is the outlier at 2.2 from 66 reviews, only one of them from the past year. All of these reviews are of Email on Acid; I found no ratings for Mailgun Inspect yet.

Reviewers like how fast they can see an email across clients, and one G2 reviewer found it more “reasonably priced than competitors like Litmus”. The complaints: G2’s summary notes that preview accuracy can vary on certain devices, a freelancer on Trustpilot found the monthly fee too steep “just to test a few emails per month”, and a Reddit thread objects to losing unlimited previews.

Email on Acid fits email developers, in-house marketing teams and agencies who design HTML campaigns in an ESP and want a monthly plan they can buy without a sales call. Unlimited seats make it easy to give every reviewer a login.

Look elsewhere if you test heavily across every client, because 1,000 previews go fast at 100 per full run. And cold email needs a different check: a short plain-text email from a Google or Microsoft inbox has little to render, and whether it lands depends on separate domains, low volume per inbox, warmup and a clean list (more in cold email infrastructure).

• Litmus: the long-time rival, now sold through sales as part of Validity Engage. Its last public plan, Core, was $500 a month in 2025, and it adds inbox placement and monitoring. See the Litmus profile.
• Mailgun Optimize: from the same owner, for placement tests instead of previews. Pilot is $49 a month with 25 tests, and Starter is $99 with 50 tests plus blocklist monitoring. See the Mailgun profile.
• ZeroBounce ONE: $99 a month for 10,000 email validations, 100 inbox placement tests and 10 blacklist monitors. See ZeroBounce.
• Instantly: cold email senders on Instantly can add its Inbox Placement tests for $47 a month, or $97 with automated tests. See Instantly.
• Reachkit (our product): if you were checking cold emails for spam, Reachkit has a free spam checker for content and sets up the sending side for you: new domains at $15 a year, warmed Google or Microsoft inboxes at $5 a month each, and 20 emails per inbox a day by default, from $39 a month. It doesn’t render HTML across clients or run placement tests.