Encode and decode Base64 in your browser
Paste text to convert it to Base64, or paste Base64 to decode it back to text — instantly, with the result updating as you type. Switch direction with one click, toggle URL-safe output, and copy the result. Everything runs in your browser: no upload, no signup, and it works offline.
What is Base64 and when do you need it?
Base64 encodes data using 64 printable ASCII characters so it can pass safely through systems built for text — email attachments, data: URLs, JSON and JWT tokens, HTTP Basic Auth. Because every 3 bytes become 4 characters, Base64 output is about 33% larger than the input (RFC 4648). It is a transport format, not compression and not security.
Encode vs. decode, and URL-safe mode
- Encode turns plain text into Base64.
- Decode turns Base64 back into the original text.
- URL-safe swaps
+and/for-and_and removes=padding, so the value works inside URLs and filenames.
The decoder accepts both standard and URL-safe input, ignores line breaks and fixes missing padding automatically.
Base64 is not encryption
This is worth repeating: Base64 offers zero confidentiality. Anyone can decode it in a second. Never store passwords, API keys or personal data as "protected" just because they're Base64 — use real encryption. Base64 only makes binary data text-safe.
Correct with UTF-8
Text is read as UTF-8 before encoding, so umlauts (ä, ö, ü), accents and emoji survive the round trip exactly. The whole process happens locally with your device's own resources — your text is never sent anywhere.