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Number Base Converter

Convert numbers between binary, octal, decimal, hex and base58. Any size, in your browser.

How It Works

1

Type a number

Enter it in any of the five bases. Prefixes 0x, 0b and 0o are understood, and spaces and underscores are ignored.

2

Say which base it is in

Pick binary, octal, decimal, hex or base58 under the field. A prefix such as 0xFF overrides the pick.

3

Copy the base you need

The number appears in all five bases at once, each with its own copy button.

FAQ

Type the hex value, such as ff or 0xFF, and pick Hex. The Decimal row shows 255. Going the other way, type 255, pick Decimal, and read the Hex row.
Any size. The conversion uses arbitrary-precision integers, so a 256-bit hash value or a 64-bit ID converts exactly, with no rounding.
No. It converts whole numbers, positive or negative. 3.14 is not a valid input.
The number written with the Bitcoin base58 alphabet (no 0, O, I or l). It converts the number as an integer. A base58 string that encodes raw bytes, such as a Bitcoin address, also counts leading zero bytes as leading 1 characters, which an integer conversion does not keep.
No. The conversion runs in your browser. To turn text rather than numbers into another encoding, use the Base64 encoder.

Built & Maintained by Varstatt

Varstatt is a one-person product studio run by Jurij Tokarski, product engineer since 2011. These tools are free and open — no signup, no catch.