Base62 encode and decode
Encode text to Base62 with digits and letters, and decode it back.
Base62 encode and decode
Base62 turns data into a compact string built from just 62 characters — the digits 0-9, the uppercase letters A-Z and the lowercase letters a-z, in exactly that order. Because it uses only letters and numbers, a Base62 value carries no +, /, = or other punctuation, so it drops straight into a URL, a filename or a database key without any escaping. That is why short-link services, content IDs and other systems that need a terse, URL-safe token reach for Base62 rather than Base64.
Pick a direction and paste your text. Encoding takes the UTF-8 bytes of your input and treats them as one big number, which it rewrites in base 62; leading zero bytes are preserved as leading 0 characters, so the value round-trips byte-for-byte. Decoding reverses the process and renders the bytes back as text. Whitespace and line breaks in a pasted value are ignored, and the first character outside the alphabet is named in the error, so a stray symbol is easy to find.
Two honest limits are built in. If the decoded bytes are not valid UTF-8 text, the tool says so instead of printing garbage — a decoded hash or raw key is binary, not a sentence. And because base conversion has no byte-aligned block, its cost grows steeply with size, so inputs are capped at 100 kB with a clear message rather than a frozen tab.
Everything runs locally in your browser. Nothing you paste is uploaded, stored or sent anywhere — the conversion happens on your own device. Copy the result or download it as a .txt file.