Compress video for email
Attachment limits lie — encoding overhead inflates files in transit. These presets are sized so your video sends on the first try.
Drop your video here
or
MP4, MOV, WebM, MKV, AVI and more — any size, no upload
🔒 Files never leave your device — everything runs in your browser.
Every email provider advertises an attachment limit — Gmail 25 MB, Outlook 20 MB, Yahoo 25 MB — and every one of them bounces files that seem comfortably under it. The culprit is transport encoding: email converts binary attachments to text (base64), inflating them by roughly a third. A "24 MB" video is a 32 MB email, and back it comes.
The presets below bake that math in: Gmail-safe targets 18 MB and Outlook-safe 15 MB, the largest sizes that reliably clear each provider's check after inflation. Compression happens entirely in your browser — handy when the video you are emailing is sensitive, because it never leaves your machine until you hit Send.
How it works
- Drop your file
Any common format, any size. Nothing is uploaded — the tool runs in your browser.
- Pick your target
Use the presets above — this page's defaults are tuned for compress video for email — or type any size.
- Download
Your converted file is ready on your device — nothing to wait for, nothing to delete from a server.
Frequently asked questions
What are the real attachment limits of major providers?
Gmail and Yahoo advertise 25 MB, Outlook.com 20 MB — but these measure the encoded message, not your file. After base64 inflation (~33%), the practical file ceilings are about 18 MB for Gmail and 15 MB for Outlook. Corporate mail servers are often stricter still, commonly 10 MB.
The recipient's server rejected it even though mine sent it — why?
Limits apply on both ends: your provider's sending cap and the recipient's receiving cap. If you are emailing a company address, assume 10–15 MB to be safe, or use the Outlook-safe preset.
When should I use a link instead of an attachment?
Past a couple of minutes of footage, a Drive or Dropbox link is kinder to everyone's mailbox. For short clips, an attachment the recipient can open instantly — no login, no link expiry — is usually the better experience.
Is my file uploaded to a server?
No. ConvertUno runs entirely in your browser on your own device. Your file never leaves your computer or phone — there is no upload at all.
Is it really free, with no watermark?
Yes. Processing happens on your device, so serving you costs us almost nothing — no watermark, no account, no file-size limit, no daily quota.