Base62 to file.

Base62 writes a number with all 62 letters and digits, 0 to 9, A to Z then a to z, and no symbols. It is the densest alphabet that needs no escaping anywhere: not in a URL, a file name, a JSON string or a shell. The tool treats the input bytes as one big number and writes that.

The bytes are read as one integer, big end first, and written in base 62 by repeated division. Each character carries about 5.95 bits, so the output is about 34% larger than the input, close to Base64. Leading zero bytes are kept as leading 0 characters. There is no padding.

URL shorteners (bit.ly's slugs), short unique ids, invite and referral codes, session and API tokens, and anywhere a 64-bit id has to become an 11-character string that fits a URL untouched.

Yes: letters and digits only, nothing to escape.

Nearly as short as Base64 with none of its symbols, which is why web ids use it; but case-sensitive, so a person transcribing it can slip, and converted as one number, so it is slow on anything big. Base58 drops the look-alike characters for the same job; Base36 drops case; Base64 streams.

No. Base62 is an encoding, not encryption: it changes how bytes are written, not who can read them, and anyone can decode it with no key. Encrypt first (AES, age, a library's sealed box) when the content needs protecting, then encode the ciphertext if it has to travel as text.

Paste the Base62 into the input, or drop a text file that holds it. The tool decodes the bytes, says what they look like and how many there are, and shows the image when they are one. Check the file name, which is guessed from the bytes, and press Download.

From the first bytes. Most formats start with a signature, 89 50 4E 47 for PNG, %PDF for PDF, PK for ZIP, and the tool knows the common images, documents, archives, fonts and media, and tells text from the rest. It is a guess for the file name only; if you know what the bytes are, rename the file and it downloads under that name.

Usually the Base62 was cut short or carries something extra. Copy the whole value, including its end; leave out quotes and commas from the surrounding code. If the status line says the bytes look like text when you expected an image, the value wasn't the file's Base62 to begin with.

Nothing leaves your browser. The text is read into memory on your machine and the encoding is computed there, in plain JavaScript; the page makes no request with it. Load the page, go offline and it keeps working.

No. The "Base62 to file" tool is free and opens without a sign-in, an account or an install.

Nothing. The "Base62 to file" tool holds your input in the page's memory, so closing or reloading the tab clears it, and it saves nothing in this browser.

Yes: you can rename it before downloading. The default name is decoded plus the extension the format suggests, such as decoded.png.

When the bytes start like a PNG, JPEG, GIF, WebP, AVIF, ICO, BMP or SVG image, the page shows a preview before you download it. Other types show their size and the name of the format they start like.

The decoder takes digits and letters in either case, and reads a leading 0 as a zero byte. Base62 treats the text as one number, so the tool takes up to 512 KB of data at once.

Closest to the "Base62 to file" tool: File to Base62, Base62 decoder, Base62 encoder, Base58 to file. Each opens on its own page, free and in the browser.

The "Base62 to file" tool is one of 32 in its group. The group's page, /tools/encoding, lists them all.

The tool is free. Its interface is built from shadcn.io's own components (Button, Input, Slider and the rest of the registry under /ui), which come in React, Vue, Svelte and Solid. Pro adds the blocks and templates for the product around it.