Free Base64 Encoder & Decoder
Base64 Encoder & Decoder converts text and files to Base64 or data URIs and back. Text can use UTF-8, UTF-16LE or ISO-8859-1, with options for the URL-safe alphabet, padding and 76-column MIME wrapping. The decoder reports the first invalid character and recognizes common file types; files can be up to 100 MB.
- Charsets:
- UTF-8, UTF-16LE, ISO-8859-1
- Variants:
- Standard and URL-safe
- File limit:
- Up to 100 MB
- Price:
- Free
- Runs:
- Locally, in your browser
- Uploads:
- None: files never leave your device
- Account:
- Not needed
Quick answers
Is Base64 encryption?
No. Base64 only re-writes bytes as text so they survive email, JSON or URLs. Anyone can decode it: never use it to hide secrets.
What is URL-safe Base64?
A variant that uses - and _ instead of + and / (and often drops the = padding), so the result can sit in URLs and file names. The decoder accepts both variants.
Processed on your device: your files are never uploaded. How it works
Network activity in this tab
What this page has requested since you opened the site in this tab. An upload is any request that sends data: POST, PUT, PATCH or a request with a body.
No uploads: nothing has been sent from this page.
No network requests yet.
To see every request, open your browser's developer tools (Network tab).
How to use the Base64 Encoder & Decoder
- Pick Text or File mode.
- In Text mode choose Encode or Decode, the character set and options such as URL-safe or line wrapping: the result updates as you type.
- In File mode drop a file to get its Base64 or data URI, or paste Base64 to download it back as a file.
Credits & open source
Built from scratch on web standards. Thank you to the people who make these projects.
Web platform APIs used: TextEncoder, File API, Clipboard API.
Full license texts: third-party notices · all credits
Frequently asked questions
Why does the decoded text look garbled?
The bytes may be a file (an image, a PDF…) rather than text, or text in another character set. The tool detects common file types, shows a preview for images and a hex dump of the bytes.
Are my files uploaded?
No. Encoding and decoding happen in your browser and files never leave your device.