Hex to Decimal Converter
Convert between hexadecimal, decimal and binary, with big-integer support for full 256-bit Ethereum values. Type into any field to update the others.
8-bit value, fits in 1 byte.
Hex, decimal and binary
The same integer can be written in different bases. Hexadecimal (base 16) is compact and maps cleanly onto bytes, which is why Ethereum uses it for addresses, hashes and calldata. Decimal (base 10) is how humans usually read numbers, and binary (base 2) is what the machine works in.
Two hex characters encode one byte. A 32-byte word, the EVM's native size, is 64 hex characters, or a 256-bit binary number. This converter keeps full precision across all three so nothing is rounded.
Frequently asked questions
How do I convert hex to decimal?
Type a hex value (with or without the 0x prefix) into the Hexadecimal field. The decimal and binary equivalents update instantly.
Does it handle 256-bit Ethereum values?
Yes. The converter uses native BigInt, so it handles full 256-bit words like uint256 balances and storage slots without losing precision.
Why does my hex have a 0x prefix?
0x marks a value as hexadecimal, the convention across Ethereum and most programming languages. You can paste values with or without it here.
Are negative numbers supported?
This tool works with non-negative integers, which covers addresses, hashes, calldata words and unsigned integers. For signed values, convert the two's-complement word first.
Building on Ethereum?
Run your code on the node itself. No rate limits, no compute units, flat rate, sub-10ms RPC.