Skip to main content

string too large for WhatsApp

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

Tool:Base64 Encoder / Decoder

Most people hit this exact problem at least once: 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.

Launch the tool: Base64 Encoder / Decoder — 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. Here's the practical workflow.

How to bring a string under 100MB

  1. Open Base64 Encoder / Decoder in any modern browser. Nothing installs.
  2. Drag the string onto the drop zone. Multiple files work too; Base64 Encoder / Decoder 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 — Base64 Encoder / Decoder 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.

Open the tool

Base64 Encoder / Decoder →

Runs entirely on your device using open web standards.

Frequently asked questions

Is there a way to do this from my phone?

Yes — open Base64 Encoder / Decoder in mobile Safari or Chrome and drop the string 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 string that's exactly 100MB on disk will sometimes still bounce.

Does Base64 Encoder / Decoder upload my string to a server?

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

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.

Related guides

Ready to try it?

Launch the tool: Base64 Encoder / Decoder. Runs entirely on your device using open web standards.

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.