Is the Number Base Converter free?

Yes. Convert as many numbers as you like, free on TheToolss.

Does it handle large numbers?

Yes. It uses JavaScript BigInt, so it handles integers of any size without precision loss.

Can I enter hex with a 0x prefix?

Yes. Leading 0x, 0b, or 0o prefixes are stripped automatically.

There is no practical limit — BigInt can represent arbitrarily large integers.

Yes. Conversion runs in your browser and nothing is uploaded.

Number Base Converter

Convert numbers between decimal, hex, octal, and binary.

100% free
Private in browser
No signup
No watermarks

Input base

Number

All bases

Decimal

—

Binary

—

Octal

—

Hex

—

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About Number Base Converter

Number Base Converter on TheToolss converts any integer between decimal, hexadecimal, octal, and binary in real time. Enter a number in one base and instantly see it in all four. It uses BigInt under the hood, so very large numbers work without precision loss. Perfect for developers inspecting memory addresses, debugging bitfields, or just double-checking a hex-to-decimal conversion. Runs entirely in your browser.

How to use Number Base Converter

Choose the input base: decimal, hex, octal, or binary.
Type or paste your number.
Read and copy the converted values in all four bases.

Key features

Decimal, hexadecimal, octal, and binary
BigInt support — no precision loss on large numbers
Copy any individual result
Instant live conversion
Private browser tool — no signup

Frequently asked questions

Is the Number Base Converter free?: Yes. Convert as many numbers as you like, free on TheToolss.
Does it handle large numbers?: Yes. It uses JavaScript BigInt, so it handles integers of any size without precision loss.
Can I enter hex with a 0x prefix?: Yes. Leading 0x, 0b, or 0o prefixes are stripped automatically.
Is there a limit?: There is no practical limit — BigInt can represent arbitrarily large integers.
Is my data private?: Yes. Conversion runs in your browser and nothing is uploaded.

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