Base64 encode/decode · Guide
Base64 Encoder and Decoder Online
Base64 turns arbitrary text or bytes into an ASCII-safe string and back again. An online encoder/decoder makes the round trip instant, and a good one handles Unicode without corrupting characters.
What Base64 is for
Base64 represents binary or text data using 64 safe characters, so it can travel through systems that only accept plain text — email bodies, JSON fields, data URLs and basic-auth headers. It is encoding, not encryption: anyone can decode it.
This tool encodes and decodes in the browser using TextEncoder and TextDecoder, so emoji and non-Latin scripts survive the round trip intact.
Encode or decode
Pick a direction, paste your input, and copy the result. Encoding takes readable text to Base64; decoding takes Base64 back to text. If decoding fails, the input is usually not valid Base64 — check for stray spaces or missing padding.
Keep it local
Because the work happens client-side, you can safely decode tokens or snippets without sending them to a third-party server.
Frequently asked questions
Is Base64 secure?
No. Base64 is reversible encoding, not encryption. Never use it to protect secrets — anyone can decode it instantly.
Why did decoding produce garbled text?
The input was probably not valid Base64, or it was Base64url (using - and _) rather than standard Base64. Check the format and padding.
Ready to try it?
Open the free browser-based Base64 encode/decode and apply what you just read — no sign-up, runs locally.
Open the Base64 encode/decode tool