Base64 Encoder & Decoder
Developer utilities · Done in 3 steps
- 1Choose a mode
- 2
- 3
About
Encode text or files to Base64 and decode it back, UTF-8 safe, with URL-safe output, data: URLs and binary file download.
How to use it
- 1Choose Encode text, Decode or File → Base64.
- 2Paste text or Base64, or drop a file.
- 3Tick URL-safe for tokens and URLs, or data: URL for embedding files.
- 4Copy the result, or download decoded binary files.
- You give
- Text, Base64 strings (standard, URL-safe or data: URLs) or any file up to 50 MB
- You get
- Base64 text, decoded text, or a downloadable decoded file
- Good to know
- Files are limited to 50 MB to keep the page responsive; Base64 output is about 33% larger than the original. Decoded binary is shown as a hex preview and offered as a download.
- Privacy
- Processed on your device. Nothing is uploaded, stored or logged.
- Last tested
- 2026-10-28
FAQ
Why does btoa() fail on my text but this works?
The browser's built-in btoa only handles Latin-1. This tool encodes text as UTF-8 first, so emoji and accented characters round-trip correctly.
What is URL-safe Base64?
A variant that uses - and _ instead of + and / and drops the = padding, so it can be used in URLs, filenames and JWTs without escaping.
Is Base64 encryption?
No. It's an encoding anyone can reverse. Never use it to hide passwords or secrets.
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