Base64 Encoder & Decoder
Encode text to Base64 or decode Base64 back to plain text, with full Unicode support.
Free Base64 encoder and decoder
A Base64 encoder converts text into the Base64 format, and a decoder converts it back. ProseTool's Base64 tool handles both directions with full Unicode support, entirely in your browser. Switch between encode and decode, paste your data, and copy the result — no signup, no uploads.
Base64 represents data using a safe set of 64 characters, which lets binary and text travel cleanly through systems that only accept plain ASCII. It is everywhere in modern computing: embedding images in stylesheets, encoding credentials, packing data into URLs, and storing small blobs in JSON. This tool makes converting to and from Base64 instant.
How to use the Base64 encoder and decoder
- Choose Encode to Base64 or Decode from Base64.
- Type or paste your input — the result appears instantly.
- If decoding fails, an error message explains that the input is not valid Base64.
- Click Copy result to take the output.
Features
- Two-way conversion between plain text and Base64.
- Full UTF-8 support so emojis and accents survive the round trip.
- Live updates as you type, with no length limit.
- Clear errors when Base64 input is malformed.
- Completely private — runs locally and never uploads your data.
Benefits of Base64 encoding
Base64 lets you move data safely through channels that were designed for text. Encoding an image as Base64 embeds it directly in HTML or CSS, removing a separate request. Encoding text protects characters that would otherwise be mangled by email or URL handling. Decoding lets you read and verify Base64 values you encounter in tokens, data URIs, and configuration.
Because the conversion uses the browser's native functions and keeps everything on your device, you can encode or decode sensitive values — tokens, keys, and personal data — without sending them anywhere. The tool handles Unicode correctly, so international text is never corrupted in the process.
Frequently asked questions
What is Base64?
Base64 is a way of representing binary or text data using only 64 safe ASCII characters (A–Z, a–z, 0–9, + and /). It is widely used to embed images in CSS, send data in URLs and emails, and store small payloads in text-only formats.
Does it support emojis and accents?
Yes. The tool encodes text as UTF-8 before converting to Base64, so emojis, accented letters, and other Unicode characters are handled correctly in both directions.
Why did decoding fail?
Decoding fails if the input is not valid Base64 — for example if it contains characters outside the Base64 alphabet or has incorrect padding. Make sure you pasted the complete, unmodified Base64 string.
Is my data private?
Yes. Encoding and decoding run entirely in your browser. Nothing you enter is uploaded, logged, or stored.