Base64
Encode or decode text and files locally.
About this tool
Encode and decode Base64 - the universal way to represent binary data as text. Used in JSON payloads, JWTs, data URIs, email attachments (MIME), HTTP Basic auth, and many other places where you need to ship bytes through a text-only channel.
Privvert handles both text and file inputs and supports the URL-safe Base64 variant (replaces + and / with - and _) for use in URLs and JWTs. Everything runs locally - confidential data never leaves your browser.
Features
- Encode and decode strings
- Encode and decode files
- Standard or URL-safe Base64
- Auto-detect input direction (heuristic)
- Live two-way conversion
- Browser-only - data never uploaded
- Free and unlimited
- Switches between standard and URL-safe alphabets in one click
How to use it
- Paste text, or drop in a file.
- Pick encode or decode.
- (Optional) toggle URL-safe mode.
- Copy the result.
Everything happens inside your browser using JavaScript and WebAssembly. Your files are never uploaded to a server, never stored, and never seen by us.
Frequently asked questions
Standard Base64 uses + and / which have special meanings in URLs. URL-safe Base64 swaps them for - and _ so the value can sit safely in URLs and JWTs.
Base64 decode produces raw bytes. If the original was binary (an image, a file), the bytes won't be readable text. If the original was UTF-8 text, the result should be readable.
No - Base64 is encoding, not encryption. Anyone can decode it. Use it for transport, not for hiding data.
For files, anything that fits in your browser's memory - typically up to several hundred MB without trouble.
Standard Base64 uses + and / characters, which have special meaning in URLs. URL-safe Base64 substitutes - and _ instead, so the output can be dropped into a URL without further escaping. The two are otherwise identical.
Yes - drag a file into the input area and the tool will encode the raw bytes. The result is a long string suitable for embedding in CSS data URIs, JSON payloads or test fixtures.