Number Base Converter

Convert between binary, octal, decimal and hex — and any base from 2 to 36. Type in one, the rest update live.

Stays on your device. This tool runs in your browser — nothing you paste or open ever leaves it. Nothing uploaded, nothing to leak.

Binary

Octal

Decimal

Hex

Any base

How to convert between bases

Type a value into whichever base you have — binary, octal, decimal or hex — and the other three update live. Use the custom-base field for anything else (base 3, base 32, and so on, from 2 to 36). Invalid digits for the chosen base are flagged rather than silently misread.

Number Base Converter — TechWhack Score

9.5/10

Privacy 10/10

Conversion runs in your browser — nothing is uploaded.
Speed 10/10

Every base updates the instant you type in any one.
Features 8/10

Shows binary, octal, decimal and hex side by side, plus a custom field for any base from 2 to 36.
Free 10/10

No sign-up, no daily limit, embeddable.

Verdict: Type into any base and the rest update live — plus any custom radix from 2 to 36 in the same view.

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A number base converter rewrites a number in a different base (radix). TechWhack shows binary, octal, decimal and hexadecimal side by side — type into any one and the others update instantly — plus a custom field for any base from 2 to 36. It all runs in your browser.

Why bases matter

Computers count in binary (base 2); programmers lean on hexadecimal (base 16) because it maps cleanly to bytes and is far shorter to read than long binary strings. Decimal is base 10, what we use day to day. Converting between them is constant work in low-level code, color values, permissions and file formats.

FAQ

How do I convert between binary, decimal, and hexadecimal?Type a value into any field and binary, octal, decimal, and hex update side by side instantly. You can also set a custom base from 2 to 36 when you need something beyond the common four.

Why is it flagging my number as invalid?Each base only allows certain digits, so a 2 is invalid in binary and a letter above F is invalid in hex. The tool flags out-of-range digits so you can correct the input for the base you chose.

Can it handle negative numbers or two's complement?Not currently. It converts unsigned values and does not yet offer two's-complement or fixed bit-width representations. For signed binary at a specific bit width you would need a specialized calculator.

What does a custom base like base 36 represent?Base 36 uses digits 0-9 followed by letters A-Z, giving 36 symbols, which is handy for compact alphanumeric IDs. Any base from 2 to 36 is supported, all converted live in your browser.