Encode a String to Base64
Encode any text string to Base64 online. Paste your text and copy the result instantly. Supports UTF-8, free and processed in your browser.
Part of the free Base64 Encoder. Runs in your browser — nothing is uploaded.
Encode a String to Base64
Base64 represents bytes using 64 printable characters. Type or paste text and get the encoded string straight away, with correct UTF-8 handling so accented characters and emoji encode properly.
Worked example: Encoding a simple greeting
Text
Hello, World!
Base64
SGVsbG8sIFdvcmxkIQ==
Practical tip
Base64 output is about 33% larger than the input, and ends with = padding when the byte length is not a multiple of 3.
How to use this Base64 Encoder
- 1Use the live tool above — it runs entirely in your browser and never uploads your data.
- 2Paste the sample from the worked example, or use your own input.
- 3Copy the result, then adapt the same steps in your editor, script, or pipeline.
Encode a String to Base64 FAQs
Why does Base64 end with ==?
Base64 works on groups of 3 bytes. When the input is not a multiple of 3, one or two = characters pad the final group.
Is my text uploaded anywhere?
No. Encoding is done locally in your browser, so nothing you type is sent to a server.
More Base64 Encoder pages
- Base64 Encode UTF-8 Text and EmojiEncode Unicode text, accents and emoji to Base64 correctly. Avoid the btoa "Invalid character" error by encoding as UTF-8 first.
- Base64URL Encoder (URL-Safe Base64)Encode text to URL-safe Base64 (Base64URL) with - and _ instead of + and /, and no padding. The format used in JWTs and URLs.
- HTTP Basic Auth Header GeneratorGenerate an HTTP Basic Authorization header by Base64-encoding username:password. Build the header for curl, fetch and Postman.
- Encode JSON to Base64Encode a JSON object to Base64 for headers, query strings and config values. Paste JSON and copy the encoded string. Free and local.
- Base64 Encode in JavaScriptEncode a string to Base64 in JavaScript with btoa() in the browser or Buffer in Node.js. Check your result with the encoder before shipping.
- Base64 Encode a URLBase64 encode a URL to pass it safely as a parameter, hide it from casual reading or store it in a single token. Use Base64URL for safer links.
- Base64 MIME Encoding With 76-Character LinesMIME Base64 wraps lines at 76 characters. See what wrapped output looks like for email attachments and PEM-style data.
- Base64 Encode in PythonEncode a string to Base64 in Python with base64.b64encode. Remember to encode to bytes first and decode the result. Verify with the online encoder.
- Base64 Encoding Without PaddingEncode to Base64 without = padding characters. See when padding is optional, how to add it back, and why JWTs omit it.