Base encoder / decoder
Encode and decode Base64, Base62, Base36
Enter plain text to encode, or a Base64/Base62/Base36 string to decode.
This tool runs entirely in your browser. Your text is never uploaded or sent to a server.
About this tool
Base encoding converts binary data into a text-safe representation using a restricted set of printable characters. Base64 is the most common — it represents binary using 64 ASCII characters and is used extensively for encoding binary data in contexts that only support text, such as email attachments, data URIs, and HTTP Basic authentication headers. Base62 uses alphanumeric characters only (no `+` or `/`), making it suitable for URLs and short codes. Base36 uses digits and lowercase letters.
Common uses
- › Encoding binary data or files for transmission in JSON or XML
- › Decoding Base64-encoded images or files from an API response
- › Creating URL-safe short codes using Base62
- › Encoding authentication credentials for HTTP Basic auth
- › Generating compact identifiers from numeric IDs using Base36 or Base62
Example
Hello, world!Base64: SGVsbG8sIHdvcmxkIQ==Technical notes
- › Base64 encoding increases data size by roughly 33%, since every 3 bytes of input become 4 output characters.
- › Encoding is not encryption — anyone can decode it instantly with no key required, so never use it to hide sensitive data.
- › Standard Base64 uses + and / characters, which have special meaning in URLs; use URL-safe Base64 (replacing them with - and _) or Base62 if the encoded string will appear in a URL.
- › Base36 and Base62 in this tool treat the input as a single large number derived from its byte values, which is why they're better suited to short strings or numeric IDs than long text.
FAQ
Is Base64 encryption?
No. Base64 is a reversible encoding scheme with no key or secret involved — anyone can decode Base64 text instantly. It's meant for safely representing binary data as text, not for security.
Why does my Base64 string end with = signs?
The = characters are padding, added when the input length isn't a multiple of 3 bytes, so the encoded output aligns to a multiple of 4 characters as the format requires.
Which base should I use for a short URL code?
Base62 is usually the best fit — it uses only letters and digits with no symbols that need escaping in a URL, unlike standard Base64's + and / characters.