Base64 Repair Tool

Got a broken Base64 string? Paste it in and let the tool automatically fix common issues like invalid characters, missing padding, whitespace, and more.

Last Updated: September 2026
100% Client-Side — Your data never leaves your device

Paste a malformed Base64 string above to repair it

Why this tool is safe

Your data never leaves your device — everything runs in your browser.

No server uploads. Other tools send your files to their servers. Ours don't.
Zero tracking of content. We never see, store, or log anything you convert.
Works offline. Once loaded, the tool works without an internet connection.
No account required. Instantly use all tools completely free without signing up.

Frequently Asked Questions

Search below or browse through our most commonly asked questions.

It automatically calculates and appends missing '=' padding, strips completely invalid characters, and attempts to recover the closest valid Base64 string.
If the string only lacked padding, no data is lost. If illegal characters were stripped, the resulting binary might differ from the original intended data.

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