Number Base Converter

How to use Number Base Converter

1. Open Number Base Converter — it runs entirely in your browser with no setup.
2. Paste or type your input into the text area, or upload a file where supported.
3. Set any options you need. The result appears in the output panel — there is no upload step and no waiting on a server.
4. Review the output instantly; large inputs are handled locally without lag.
5. Copy the result to your clipboard or download it. Your data never leaves the page.

Why use Number Base Converter?

• 100% free with no limits, no sign-up and no watermarks.
• Private by design — your data are processed in your browser and never uploaded to a server.
• Fast and lightweight, with instant results even on a phone or a slow connection.
• Works everywhere — any modern browser on Windows, macOS, Linux, Android or iOS.
• Part of a full programming suite, so related binary tasks are one click away.

What people use Number Base Converter for

• Converting between binary, octal, decimal and hexadecimal.
• Reading a hex value from a memory dump or a colour code.
• Checking a conversion while debugging low-level code.

Number Base Converter: limits and things worth knowing

• One hex digit represents exactly four bits, which is why hexadecimal is used for binary data — a byte is always exactly two hex digits.
• Prefixes signal the base in most languages: 0x for hex, 0b for binary, 0o for octal. A leading zero alone means octal in C and several older languages, which is a genuine source of bugs.
• Hex letters A-F are case-insensitive as values, though conventions differ by context.
• Negative numbers in binary are normally represented in two's complement, so the raw bit pattern of −1 in eight bits is 11111111 rather than a sign bit plus magnitude.

Is it private and secure?

Your privacy is built in. Number Base Converter runs completely on your device, so whatever you enter stays in your browser and is never transmitted, logged or stored on any server.

Network activity: none. Nothing is sent and nothing is fetched. This tool makes no network request at all once the page has loaded — which is why it keeps working if your connection drops.

You do not have to take that on trust — our privacy proof page publishes the Content-Security-Policy that enforces it, lists every third party it permits, and shows how to verify the whole claim yourself.

Learn more

Why Browser-Based Tools Are Safer for Your Files — Most online converters upload your files to a server. Client-side tools don't. Here's why that difference matters for privacy.