Base58 encoder.

Base58 is Bitcoin's alphabet, written by Satoshi Nakamoto in 2009: the 62 letters and digits without the four that look alike, 0 (zero), O (capital o), I (capital i) and l (lowercase L). It exists so that an address copied by hand, or read from a screen, is not mistyped. The tool treats the input bytes as one big number and writes it.

The bytes are read as one integer, big end first, and written in base 58 by repeated division; each leading zero byte becomes a leading 1, the alphabet's zero digit. Each character carries about 5.86 bits, so the output is about 37% larger than the input. There is no padding.

Bitcoin addresses and private keys (as Base58Check, which adds a version byte and a four-byte checksum), IPFS content ids that start with Qm, Solana account keys, Monero and Ripple addresses (Ripple with its own alphabet order), and short ids where people copy by hand.

It gives up a little density (37% against Base64's 33%) and a lot of speed (the whole input is one number) for strings a person can transcribe without error. Use it where people read and type the value; use Base64 where only machines do.

Probably a different alphabet or a checksum. Bitcoin's order (1 to 9, A to Z, a to z, minus the look-alikes) is the one here, and Flickr and Ripple reorder it. A Bitcoin address is Base58Check: the tool decodes it to its raw bytes, including the version byte and the four-byte checksum at the end, and doesn't verify the checksum.

No. Base58 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.

Type or paste into the input and the Base58 appears as you type: "hello" becomes Cn8eVZg. Text is encoded as UTF-8 bytes, so accents and emoji come out the same as in every language's standard library. Copy the result, download it as a text file, or press Swap to decode it back.

Drop a file onto the input or choose one with the button, and its bytes are encoded directly, not as text. Base58 treats the whole input as one number, so the tool takes up to 512 KB at once; past that the conversion would stall the page.

Nothing leaves your browser. The text or file 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 Base58 encoder is free and opens without a sign-in, an account or an install.

Nothing. The Base58 encoder holds your input in the page's memory, so closing or reloading the tab clears it, and it saves nothing in this browser.

None: Base58 has a single alphabet, so the encoder has no choices to make.

Base58 output is about 1.37 characters per byte, and the status line under the result shows the bytes in, the characters out and the percentage. Base58 treats the input as one number, so the tool takes up to 512 KB at once.

The text is encoded as UTF-8 bytes first, so accented letters, other scripts and emoji round-trip through the decoder unchanged. Each of those characters takes more than one byte, which makes the output longer than the character count suggests.

Press Swap once there is a result and the same tool becomes the Base58 decoder, with the output moved into the input. The decoder shows the original text again.

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

The Base58 encoder 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.