Litmus got expensive. Email review didn’t have to.
Proofel is the review-and-approval layer for HTML email: one link, pixel-pinned feedback, reviewers who never make an account, and pre-send checks on the same screen. From $19/mo, and we will tell you exactly what we don’t do.
14-day all-access trial · no credit card required · reviewers never need an account
What changed in email testing
Taken from each vendor’s own pages, as of 15 October 2026.
Litmus no longer publishes pricing
Until August 2025, Litmus’s pricing page listed a Basic plan at $99 per month. It was replaced by a single Core plan at $500 per month, and later by Enterprise only. Today the pricing page sends visitors to a contact-sales form. Litmus has been part of Validity since April 2025.
Source: litmus.com/pricing (incl. archived versions), validity.com · as of 15 October 2026
Litmus Proof is on Enterprise plans
Litmus Proof, its review and approval feature, is available on Enterprise plans. Review and approval in Proofel, including unlimited no-account reviewers, is on every plan, Free included.
Source: Validity / Litmus knowledge base · as of 15 October 2026
Email on Acid became Mailgun Inspect
Email on Acid customers began moving to Mailgun Inspect in June 2026, with annual plans moving at the end of their term. Existing previews and tests are not transferred. Mailgun Inspect plans start at $99 per month for 1,000 previews.
Source: emailonacid.com/pricing, mailgun.com/pricing/inspect · as of 15 October 2026
Our client weighting comes from Litmus’s own published email client market-share data. We think they built something good and then priced it out of reach of a lot of the people who need it.
What Proofel is not
- No real-device renders. We simulate clients; we do not run them.
- No screenshot matrix across 100+ real clients and devices. We model 20 client lenses.
- No accuracy percentage. There is no defensible way to compute one, so we do not publish one.
- No pixel-exact classic-Outlook (Word engine) render.
If real-device rendering across every client is what you are replacing, we are not that. Keep a rendering tester and use us for the part it doesn’t do.
What a simulation can tell you that a screenshot can’t
A screenshot is the truth for one machine at one moment, but it is a bitmap: the colours and CSS you wrote are gone. We transform your HTML and render the result, so every step stays inspectable.
Contrast measured inside the dark inversion
We invert your colours with a per-client model and measure WCAG AA contrast in the inverted document, so a caption that passes in light and falls to 3.1:1 in Gmail dark mode is a number, not a squint.
The declaration a client drops, named
Support is checked per CSS declaration against the caniemail dataset, so a finding says which property a client ignores rather than showing a corner that came out square.
Outlook Word-engine lint, to the line
The constructs classic Outlook mishandles are flagged where they are written in your HTML. We lint Outlook; we do not claim to position it to the pixel.
States composed, not photographed one by one
Dark mode plus images blocked at 320px is a real state real subscribers are in. Lenses stack, so you check the combination in one view.
Try it on your own email with no account: the all-in-one email checker.
The review layer is on the Free plan
One link for every reviewer. They enter a name and pin feedback on the exact element, then approve or request changes, and the decision is recorded against the version they saw. Guest reviewers are unlimited and never need an account, on every plan.
Side by side
Competitor cells come from each vendor’s own pages as of 15 October 2026. Where a vendor doesn’t say, we show a dash rather than guess.
| Capability | Proofel | Litmus | Mailgun Inspectformerly Email on Acid |
|---|---|---|---|
| Entry price | $0 Free · $19/mo Pro | Not published (contact sales) | $99/mo Basic |
| Reviewers need an account | No | Not stated by the vendor | Not stated by the vendor |
| Charged per reviewer | Never | Not stated by the vendor | Not stated by the vendor |
| Recorded approvals | Every plan | Enterprise plans (Litmus Proof) | Not stated by the vendor |
| Screenshots from real clients and devicesThe row where we lose. We simulate; they render. | No | 100+ clients and devices | 100+ clients and devices |
| Deterministic simulation across 20 client lensesContrast inside dark mode, dropped CSS named, states composed. | Yes | Not stated by the vendor | Not stated by the vendor |
We can’t import your Litmus previews. Nobody can.
Screenshots taken by another service stay with that service. What moves is the email itself, and that takes about two minutes:
- Every email in Proofel has its own address. Send a test from any ESP to it and it lands as a version.
- Or upload a saved .eml file. Nothing to connect, and your ESP stays exactly as it is.
Start free. Pro is $19 a month.
Free
$0
For getting started.
- 3 active emails and 3 campaigns
- Unlimited guest reviewers, versions and comments
- Preview in 20 email clients, desktop and mobile
- Dark-mode, blocked-image and Gmail-clipping previews
- The all-in-one email checker, free and unlimited
Pro
$19/mo
For solo creators who send a lot.
- Everything in Free, unlimited
- The full pre-send report: 100-point score, 15+ checks
- Accessibility, Outlook and 20-client support analysis
- One-click auto-fix, SpamAssassin score and test sends
- Email cleanup, Link Visualizer and version compare
- Password-protected links and multi-step approval
Common comparisons
- Is Proofel an alternative to email testing tools like Litmus or Email on Acid?
- They answer a different question, and plenty of teams use both. Litmus and Email on Acid render your email on real machines running real clients and hand back screenshots. Proofel simulates deterministically: it transforms your HTML and renders the result, which keeps the colour model and the CSS intact. That is what lets it report WCAG AA contrast measured inside a Gmail dark-mode inversion, name the exact declaration a client will drop, lint the constructs Outlook’s Word engine mishandles down to the line, and compose states (dark plus images blocked plus 320px) a screenshot service would have to photograph separately. The tradeoff is real and we publish it: no pixel-exact classic-Outlook render, and no accuracy percentage. Proofel also does the part a rendering tester does not — pixel-pinned feedback, versions, and recorded sign-off.
- Should I stop testing on real devices?
- No. Treat Proofel as the fast first pass that catches the class of problem you cannot see by eye — contrast after inversion, dropped declarations, subject truncation, Gmail clipping, blocked images — then test anything high-stakes on the real clients your list actually uses. If classic Outlook for Windows is a large share of your list, test there specifically: we lint it and tell you which CSS it drops, but we do not claim to position it to the pixel.
- How is Proofel different from generic proofing tools like Filestage or Ziflow?
- General proofing platforms review many file types (video, PDF, images) with pinned comments and approvals. Proofel is purpose-built for HTML email: it renders the real email at desktop and mobile widths, applies 20 client lenses mapped to their actual engines, models each client’s dark mode, measures contrast, checks every link, and fixes Gmail clipping — details a generic file proofer structurally cannot see.
- Does Proofel send my email campaigns?
- No. Proofel is not an email service provider. It is the review and approval layer before the send; you export the approved email as a standard .eml file or send it from your existing ESP. The one thing it does send is a test of the email to your own account address, so you can open the real message in your real mail app.
- Do reviewers need an account or a paid seat?
- No. Guest reviewers are unlimited on every plan and never need an account. Paid seats only apply to the people in your workspace who create and manage campaigns.
Keep your rendering tests. Fix the sign-off.
Bring in your next campaign and get pinned feedback, checks and a recorded approval in one link.
14-day all-access trial · no credit card required · reviewers never need an account