How large numbers are supported?

Arbitrarily large — conversions use BigInt, so precision never drops.

What does the Number Base Converter (Binary, Hex, Decimal) give me?

It works out Bit Length and Byte Size, updating live as you change the inputs.

What do I need to enter?

Just Input Number and Input Base / Radix. Every field has a sensible default you can start from.

Is my data uploaded anywhere?

No. The calculation runs in your browser with JavaScript — nothing you type is sent to a server or stored.

Does it work on a phone?

Yes. The layout adapts to small screens and needs no app or signup.

Number Base Converter (Binary, Hex, Decimal)

Convert numbers between Binary, Octal, Decimal, Hexadecimal, and any custom base.

100% free
Private in browser
No signup
No watermarks

Input Number

Input Base / Radix

Bit Length

Byte Size

1 bytes

Decimal (Base 10)

255

Binary (Base 2)

11111111

Hexadecimal (Base 16)

Octal (Base 8)

377

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About Number Base Converter (Binary, Hex, Decimal)

Convert numbers between Binary, Octal, Decimal, Hexadecimal, and any custom base. Enter Input Number and Input Base / Radix and the tool works out Bit Length and Byte Size straight away. Everything runs in your browser, so your data never leaves your device.

How to use Number Base Converter (Binary, Hex, Decimal)

Type the number to convert.
Choose the source base.
Copy any of the converted representations.

Key features

Binary, octal, decimal, hex
Custom bases up to 36
BigInt precision for huge numbers
Optional prefixes

Frequently asked questions

How large numbers are supported?: Arbitrarily large — conversions use BigInt, so precision never drops.
What does the Number Base Converter (Binary, Hex, Decimal) give me?: It works out Bit Length and Byte Size, updating live as you change the inputs.
What do I need to enter?: Just Input Number and Input Base / Radix. Every field has a sensible default you can start from.
Is my data uploaded anywhere?: No. The calculation runs in your browser with JavaScript — nothing you type is sent to a server or stored.
Does it work on a phone?: Yes. The layout adapts to small screens and needs no app or signup.

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