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string too large for WhatsApp

WhatsApp's 100MB media cap blocks bigger files. Use Image to Base64 to bring your string under the limit while keeping it readable.

Tool:Image to Base64

There's a clean fix once you know where to look: a string 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 string below that threshold before you hit Attach.

Use the tool: Image to Base64 — Runs entirely on your device using open web standards.

Why this happens

Strings 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. What follows works in every modern browser.

How to bring a string under 100MB

  1. Open Image to Base64 in any modern browser. Nothing installs.
  2. Drag the string onto the drop zone. Multiple files work too; Image to Base64 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 string 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 strings to send to the same person, drop them in together — Image to Base64 handles a batch in one click, then you attach the whole folder.

What if it's still too big?

A few strings 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 string 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.

Try it now

Image to Base64 →

Runs entirely on your device using open web standards.

Frequently asked questions

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.

Does Image to Base64 upload my string to a server?

No. Image to Base64 runs entirely in your browser using WebAssembly. The string never leaves your device — there is no server to send it to.

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 string that's exactly 100MB on disk will sometimes still bounce.

Related guides

Ready to try it?

Run it in your browser: Image to Base64. Browser-only. Nothing is sent to a server.

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.