Is Base64 encryption?

No. Base64 is an encoding: it represents bytes as 64 printable characters so binary data can travel through text-only channels. Anyone can decode it instantly, so never use it to hide passwords or secrets.

Why is Base64 output longer than the input?

Every 3 bytes become 4 characters, so encoded data is about 33% larger, plus up to two = padding characters at the end to fill the last group.

What is URL-safe Base64?

A variant (base64url, RFC 4648) that uses - and _ instead of + and /, which have special meanings in URLs, and usually leaves out the = padding. JWTs use it.

Is my code or data uploaded anywhere?

No. Every tool runs in your browser, so your code, tokens, keys and files are processed on your device and are not sent to our server or stored. Reloading or closing the page clears them.

Yes. Every tool is free with no sign-up and no limits on use. Clearly labeled ads keep it that way.

Does it work on my phone?

Yes. The tools work in any modern browser on phones, tablets and computers, though large files and long code are easier to handle on a computer.

Base64 Encode and Decode

Encode text to Base64, or decode it back.

100% Free
No Sign Up
Works in Your Browser

Base64 encode/decode

Encode and decode Base64 text

Direction

URL-safe (- and _, no padding)Wrap lines at 76 (MIME)

Text or Base64

Result

SGVsbG8sIFdvcmxkISDDnG7Dr2PDtmTDqSB0ZXh0ICYgPHN5bWJvbHM+IPCfkYs=

Encoded to Base64. 47 bytes (UTF-8) → 64 characters

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How to use the Base64 encode/decode

Three steps, all in your browser.

1
Paste your input
Type or paste your code or data. Press Sample to try an example.
2
Choose the direction
Encode or decode. Errors point at what's wrong with the input.
3
Copy the result
Copy the output in one click. Nothing is saved or sent anywhere.

Base64 Encode and Decode: what to know

This tool encodes text to Base64 and decodes Base64 back to text. Text is converted to UTF-8 bytes first, so accented letters, non-Latin scripts and emoji round-trip correctly, which isn't the case with the browser's plain btoa() function. A URL-safe option uses the base64url alphabet from RFC 4648, with - and _ instead of + and /.

Base64 represents binary data with 64 printable characters, 6 bits per character, so every 3 bytes become 4 characters and the output is about a third larger. Padding with = fills the last group. It exists so binary data can pass through systems that only handle text: email attachments (MIME), data URIs, HTTP Basic authentication headers, JSON fields holding files, and the parts of a JWT.

Base64 is an encoding, not encryption. There is no key: anyone can decode it, instantly. An API key or password in Base64 is as exposed as one in plain text, so never use it to hide secrets.

Popular uses

Decoding Base64 values in API responses and configs
Building and checking HTTP Basic auth headers
Reading Kubernetes Secret values, which are Base64-encoded
Encoding text for data URIs and email

Tips for the best result

If decoding fails, check for spaces or line breaks added when copying, and for URL-safe characters (- and _).
Base64 that decodes to unreadable characters is probably binary data, such as an image or compressed file, not text.
To turn an image into Base64, use the Image to Base64 tool instead.

Read how JustYourDev works and our privacy details. Code, data and files you use here are processed in your browser and are never sent to our server.