Number Base Converter
Convert hex, decimal, octal and binary with a clickable bit grid.
Reading flags, masks and register values means moving between hex, decimal and binary constantly. The Number Base Converter keeps all four bases in sync and lets you flip individual bits in a grid. Values are handled as arbitrary-precision integers locally, so 64-bit numbers convert exactly.
Four bases in sync
Edit hex, decimal, octal or binary and the other three update. Prefixes such as 0x, 0b and 0o, plus spaces and underscores, are accepted on input.
Selectable bit width
Choose 8, 16, 32 or 64 bits. Values wrap to the chosen width, including negative decimals.
Clickable bit grid
Every bit is a button. Click to toggle it and watch all four bases change. The sign bit is outlined and bits are numbered.
Two's complement
See the signed interpretation at the current width, alongside the unsigned value when they differ.
Grouped binary readout
The full binary value is shown padded to the width and split into groups of eight bits.
How does the converter handle negative numbers?
Enter a negative decimal and it is wrapped to the selected width using two's complement. The signed value is shown below the fields.
Can it convert 64-bit values without rounding?
Yes. Values are stored as BigInt integers, so 64-bit numbers are exact rather than rounded like JavaScript floats.
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