HTML Email Minifier
Gmail clips any message over 102 KB (104,448 bytes). This strips comments and whitespace, and leaves Outlook conditionals, <pre> and your CSS as they are.
@emailens/engine 0.18.22 · data last changed 10 Nov 2026
Example · the sample above. Paste yours to replace it.
After: 0.7% of Gmail's 102 KB clip limit.
<!DOCTYPE html> <html> <head> <title>Your receipt</title> </head> <body style="margin: 0; background: #f6f4ef;"> <table role="presentation" width="100%" cellpadding="0" cellspacing="0"> <tr> <td style="padding: 24px; font-family: Arial, sans-serif; color: #111111;"> <h1 style="margin: 0 0 12px;">Thanks for your order</h1> <p style="margin: 0;">Your order has shipped and arrives Friday.</p> </td> </tr> </table> <!--[if mso]><table role="presentation" width="600"><tr><td><![endif]--> <p style="font-family: Arial, sans-serif; font-size: 12px; color: #777777;"> Acme Goods · 48 Market Street · Portland, OR 97204 </p> <!--[if mso]></td></tr></table><![endif]--> </body> </html>Or see exactly where Gmail's clip line falls, and whether your unsubscribe link is above it: Check its size, free
Paste your own email above and check it, or open the checker and paste it there: five clients, no account.
No signup · Five clients free, Outlook Classic included · All 21 with an account
Which clients need an account
Gmail Android, Gmail iOS, Outlook 365, Outlook iOS, Outlook Android, Outlook for Mac, Apple Mail, Yahoo Mail Android, Yahoo Mail iOS, Samsung Mail, Thunderbird, HEY Mail, Proton Mail, AOL Mail, Fastmail, Superhuman open with a free account.
The checker needs a computer screen.
Your next question
- Is your unsubscribe link above Gmail's clip line? Check its size, free.
- Does the <style> block survive Gmail's apps? Inline your CSS, free.
Other free tools: Subject Line & Preheader Tester · Plain-Text Generator · AI Fix-Prompt Generator · Email Link Checker · UTM Link Builder · Accessibility Checker
Run this check on every email
The open-source CLI checks every template's size, free: npx @emailens/cli lint email.html
(CLI docs).
The 102 KB clipping check in the app (Dev). Dev is $9 a month. Share links for your client's sign-off, a test inbox and an API key. See the plans →
Questions
How does minifying fix Gmail clipping?
Gmail clips any email whose HTML exceeds 102 KB, hiding everything past the cut behind a 'View entire message' link, including tracking pixels and unsubscribe links. Minifying removes the dead weight (indentation, newlines, comments) that templating engines add, which is often enough to drop you back under the limit.
Will minifying break my email?
This minifier is deliberately conservative. It preserves Outlook conditional comments, the whitespace inside <pre> and <textarea> blocks, and leaves your style and script bodies untouched. It only collapses runs of whitespace and strips ordinary HTML comments, keeping single spaces so inline text spacing is intact.
Why is my email still over the limit after minifying?
If you're still over 102 KB, the weight is usually elsewhere: large blocks of repeated inline CSS, or base64-embedded images. Minifying HTML whitespace won't touch those. The fix is to consolidate repeated styles and host images on a URL instead of embedding them.
Does it minify my CSS too?
No, and that's intentional. Safely minifying CSS needs a real CSS parser, and a wrong move there can change how your email renders. This tool sticks to HTML whitespace and comments, where the savings are safe. To inline your CSS for clients that need it, use the CSS inliner.