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video too large for WhatsApp

WhatsApp's 100MB media cap blocks bigger files. Use WebM to MP4 to bring your video under the limit while keeping it readable.

The real reason this is annoying is rarely the file itself: a video just over the WhatsApp attachment limit, and you have to send it now.

WhatsApp's hard cap is 100MB per outgoing message. Anything bigger gets rejected — sometimes silently, more often after you've waited 30 seconds for the upload bar to crawl. The fix is to bring the video below that threshold before you hit Attach.

Use the tool: WebM to MP4 — Browser-only. Nothing is sent to a server.

Why this happens

Videos grow for predictable reasons — embedded images at full camera resolution, fonts shipped twice, scanned pages saved at 600 DPI, video clips that were never meant for email. The original was fine for archiving, but it isn't shaped for email. Here's the practical workflow.

How to bring a video under 100MB

  1. Open WebM to MP4 in any modern browser. Nothing installs.
  2. Drag the video onto the drop zone. Multiple files work too; WebM to MP4 processes them in a single pass.
  3. Pick a compression preset. "Balanced" is the right answer 95% of the time — visually identical output, file size cut by 50–80%.
  4. Wait for processing — usually under five seconds for a video smaller than 50MB.
  5. Download the result. It lands in your default downloads folder under the original filename, suffixed.
  6. Attach the smaller version to WhatsApp and send. The size badge in the attachment row should now read well below 100MB.

If you have a stack of videos to send to the same person, drop them in together — WebM to MP4 handles a batch in one click, then you attach the whole folder.

What if it's still too big?

A few videos resist compression — usually because they're already aggressively compressed, or they're video / audio at high bitrate. Two reliable next moves:

  • Trim or split. If the video is content-rich, sending half today and half tomorrow often beats forcing it into one attachment.
  • Switch to a cloud link. Google Drive, OneDrive, Dropbox, and WeTransfer all give you a copy-paste link that bypasses every mail provider's cap.

Launch the tool

WebM to MP4 →

No upload, no signup, no daily limit.

Frequently asked questions

Is there a way to do this from my phone?

Yes — open WebM to MP4 in mobile Safari or Chrome and drop the video from your photo library or Files app. The flow is identical to desktop, just with bigger taps.

Why is base64 encoding mentioned — what does that mean for me?

Email attachments are base64-encoded on the wire, which adds about 33% to the file size during transit. WhatsApp's 100MB is measured after that inflation, which is why a video that's exactly 100MB on disk will sometimes still bounce.

Why does WhatsApp reject files over 100MB?

It's a server-side rule, not a client setting. WhatsApp lifted the document cap to 100MB in 2022. Media (photos / video) still has lower per-asset limits.

What's the maximum I should attach to WhatsApp, in practice?

Stay 10–15% under the hard cap. WhatsApp's 100MB is the wire limit, but base64 encoding inflates the body by ~33%. Headroom prevents the "rejected after 30 seconds" failure mode.

Related guides


Ready to try it?

Run it in your browser: WebM to MP4. Free, no account required, no watermark.


Last reviewed May 2026. File-size limits, portal requirements, and software defaults change over time — always verify with the destination platform before uploading time-sensitive documents. References to third-party services and products are for descriptive purposes only and do not imply any partnership or endorsement.