Litmus is still the best-known way to see how an email will look before you send it. As of November 2026 it shows previews in more than 90 email clients and devices, dark mode included, and it adds accessibility and pre-send QA checks. A lot has changed since this post first ran. Validity bought Litmus in April 2025, the cheap day passes and small plans are gone, and the list of clients you need to test now centres on Apple Mail, Gmail and Outlook on phones, often in dark mode. Your emails also have to pass the 2024 Gmail and Yahoo bulk sender rules on SPF, DKIM, DMARC, one-click unsubscribe and spam rates, and the matching Outlook.com rules from May 2025.
If your email campaigns are hard or slow to test and QA, take a look at Litmus.
What Litmus does
Litmus takes screenshots of how your email (or web page) looks in every major email client. When this post was first written, it tested on these platforms:
- Outlook 2007
- Outlook 2003
- Outlook 2002/XP
- Outlook 2000
- Gmail
- Hotmail
- AOL Mail
- Yahoo! Mail
- Lotus Notes 8
- Lotus Notes 7
- Lotus Notes 6.5
- Apple Mail 3
- Apple Mail 2.1
Most of that list is history now. Here is what happened to each client family:
| Client on the original list | Where it stands in 2026 |
|---|---|
| Outlook 2000, 2002/XP, 2003 | Retired. Microsoft no longer supports them. |
| Outlook 2007 | Retired, with support ending on October 10, 2017. It used Word 2007 as its rendering engine, and classic Outlook for Windows still renders email with Microsoft Word. That is why Outlook tables and VML fallbacks still matter. |
| Gmail | Still a top client. Now has inbox tabs, an image proxy that caches images, and webmail and app versions that render differently. |
| Hotmail | Became Outlook.com, a move Microsoft announced in July 2012 and completed in 2013. The new Outlook for Windows uses the same web-based rendering. |
| AOL Mail | Still running, under Yahoo Inc. |
| Yahoo! Mail | Still running, with its own app and webmail rendering. |
| Lotus Notes 6.5 to 8 | IBM sold Notes to HCL in 2019. It is now HCL Notes and only matters for some enterprise lists. |
| Apple Mail 2.1 and 3 | Long gone. Apple Mail on iPhone, iPad and Mac is now one of the biggest clients by tracked opens. |
The modern Litmus preview list is much longer. It covers current Apple Mail, Gmail, Outlook, Yahoo and Samsung Mail versions across desktop, webmail, iOS and Android, with dark mode views. You can also build your own client lists so you only test the clients your subscribers use.
Why previews still matter
Previews are still a quick, easy way to check that your email renders well in every client you care about. The problem has changed shape, though. Old-style rendering bugs from ancient Outlook versions matter less. These matter more today:
- Dark mode. Some clients invert your colours and some don’t. Logos on transparent backgrounds and dark text on images break first. Litmus checks for the CSS
color-schemesetting and shows dark mode previews. - Mobile layouts. Most opens happen on phones, so a single-column layout that stacks well is the safe default.
- Accessibility. Litmus runs automatic accessibility checks in more than 40 categories, offers visual impairment filters, and can play an audio transcript of your email as read by the NVDA screen reader.
- Links, tracking and load speed. The QA Checks tab in Litmus Builder covers First Impressions, Accessibility, Links, Tracking and Loading Speed. It is not available in the Visual Editor view.
One caution. A clean preview does not mean you’ll land in the inbox. Inbox placement depends on authentication, complaint rates and list hygiene, and Litmus sells deliverability tools separately from previews.
Pricing then and now
Litmus used to be cheap. When this post was written it cost $18 for a day’s use, $55 a month for unlimited tests, and $185 a month for unlimited tests with 10 user accounts. Those plans no longer exist.
| Period | What Litmus offered |
|---|---|
| Original plans (late 2000s) | $18 day pass, $55 a month unlimited, $185 a month unlimited with 10 users |
| Before August 2025 | Basic and Plus tiers, with reported prices of about $99 and $199 a month (1,000 and 2,000 previews a month) |
| August 2025 overhaul | Plus became Core, reported at $500 a month with 5 users, 2,000 previews, 500,000 analytics opens and 50,000 Litmus Personalize impressions |
| 2026 | The pricing page sends you to sales. Enterprise and the deliverability add-on are quote-only. |
Previews are counted per client, every time they are generated. So if you test one email in 30 clients and fix it twice, that’s 90 previews. On a 2,000-preview allowance, that pace gets you about 22 fully tested emails a month. If you re-test after every small change, cut your client list down to what your audience actually uses.
For a solo marketer or a small store, the current prices are hard to justify. Email on Acid, now sold by Sinch Mailgun as Mailgun Inspect, lists its Basic plan at $99 a month with 1,000 previews. Many ESPs also have built-in inbox previews powered by Litmus or similar tools, so check what your current platform offers before you buy anything.
The Litmus blog
Litmus runs a blog that’s worth a look. It’s updated regularly with product news, coding guides and research, including its email client market share reports. Remember that those reports count tracked opens. Apple Mail Privacy Protection loads tracking pixels automatically, which pushes Apple’s share up, so use the figures as rough guidance and check your own ESP’s client data.
FAQ
Is Litmus still worth it in 2026?
It’s worth it for teams that send a lot of designed campaigns and need shared review, QA checks and previews in one place. For small senders, a cheaper preview tool or the previews built into your ESP usually covers the essentials. Ask Litmus sales for a quote and compare it with how many emails you actually test each month.
Which email clients should I test first?
Start with your own ESP’s client report, not industry averages. Most lists need Apple Mail on iPhone, the Gmail app and webmail, and Outlook. Test classic Outlook for Windows, the new Outlook and Outlook.com separately, because they render differently. Add a dark mode check for each.
Does a good Litmus preview mean my email will reach the inbox?
No. Previews show rendering, not inbox placement. Since February 2024, Gmail and Yahoo have required bulk senders to authenticate with SPF and DKIM, publish a DMARC record, offer one-click unsubscribe and keep spam complaint rates under 0.3%. Outlook.com started applying similar rules to senders of more than 5,000 messages a day in May 2025.
Why are my open rates so high in Litmus analytics or my ESP?
Apple Mail Privacy Protection preloads images, tracking pixel included, for users who turn it on. That records an “open” whether or not anyone read the email. Use clicks, conversions and replies as your main engagement measures, and treat opens as a rough signal.
Who owns Litmus now?
Validity, the Boston-based company behind Everest and other email data tools, bought Litmus on April 10, 2025. The price wasn’t disclosed. The product is now branded “Litmus from Validity”, and its pricing moved upmarket in August 2025.
Sources
- Litmus Help Center: Email Previews usage guide
- Litmus Help Center: Previews & QA pre-send testing guide
- Litmus Help Center: QA Checks tab in Litmus Builder
- Google Workspace Admin Help: Email sender guidelines
- Yahoo Sender Hub: Best practices
- Microsoft Tech Community: Outlook’s new requirements for high-volume senders
- FTC: CAN-SPAM Act compliance guide for business