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Number Base Converter

Binary, octal, decimal and hexadecimal — all at once.

Best for: Use it in programming, digital electronics and networking, or to read colour codes and memory addresses.

Complete guide

Input

FF
Base 16
11111111
Base 2
377
Base 8
255
Base 10
FF
Base 16
How it's calculated & sources
The Number Base Converter uses the standard, deterministic formula, so the same inputs always produce the same result. It runs entirely in your browser, so your inputs are never uploaded. Last reviewed June 2026.

Free & no sign-up · runs entirely in your browser. Results are estimates for general information, not professional advice — verify important decisions with a qualified expert. Last reviewed June 2026.

How it works

Each digit's value = digit × baseposition. Supports any base from 2 to 36 (digits 0-9 then A-Z) for both input and output.

Example

255 (base 10) = FF (base 16) = 11111111 (base 2) = 377 (base 8) = 73 (base 36).

Frequently asked questions

Which bases are supported?+

Any base from 2 to 36 for input and output — binary, octal, decimal, hex, and unusual bases like 3, 12 or 36.

Negative numbers?+

Positive integers only; two's-complement representation is not used here.

Is conversion real-time?+

Yes — values update instantly as you type in either field, with full bidirectional input.

Where does the number base reference come from?+

All factors are SI-anchored using internationally accepted conversions.

Continue your journey

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Complete guide

Quick answers

Short, sourced answers to the questions people (and AI assistants) ask most.

What is Number Base?
A number base converter changes a whole number between binary (base 2), octal (base 8), decimal (base 10) and hexadecimal (base 16).
Why does Number Base matter?
The same value written in each base - only the notation changes, not the number.
How is Number Base calculated?
The input is parsed from its base into a plain integer, then re-expressed in each target base. Formula: Each digit's place value is base^position; e.g. binary 1010 = 8 + 2 = 10; hex FF = 255.
What are common number base mistakes?
Mixing up which base the input is in.
When should you use the Number Base Converter?
Use it in programming, digital electronics and networking, or to read colour codes and memory addresses.

What is the Number Base Converter?

A number base converter changes a whole number between binary (base 2), octal (base 8), decimal (base 10) and hexadecimal (base 16).

How the Number Base Converter works

The input is parsed from its base into a plain integer, then re-expressed in each target base.

Each digit's place value is base^position; e.g. binary 1010 = 8 + 2 = 10; hex FF = 255

Number bases — decimal, binary, octal, hexadecimal

0000
1111
21022
410044
81000108
10101012A
15111117F
16100002010
321000004020
64100000010040
100110010014464
25511111111377FF
256100000000400100
1024100000000002000400

Common mistakes to avoid

  • Mixing up which base the input is in.
  • Forgetting hex uses A-F for 10-15.
  • Expecting fractional or negative handling that base tools often omit.

Keywords: binary, hex, octal, base.

Reviewed by the Free Tools Galaxy editorial team · Updated June 2026 · Calculated privately in your browser.

Frequently asked questions

Is the Number Base Converter free to use?+

Yes. Every tool on Free Tools Galaxy is 100% free, runs in your browser and requires no signup.

How accurate is the Number Base Converter?+

Number Base Converter uses the standard number base formula in double-precision arithmetic, so the same inputs always produce the same result and you can verify any figure by hand. It is an educational estimate — real-world outcomes depend on your actual rates, rules and assumptions.

Do you store my inputs?+

No. The Number Base Converter runs entirely in your browser. Nothing is uploaded or saved to a server.

Can I use the Number Base Converter on mobile?+

Yes — the interface is fully responsive and works on phones, tablets and desktops.

What are common mistakes to avoid?+

The most frequent mistake is mixing units. Double-check your inputs use a single, consistent unit before clicking Calculate.

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Number Base Converter on Free Tools Galaxy — Binary, octal, decimal and hexadecimal — all at once. https://freetoolsgalaxy.com/tools/number-base-converter
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# Number Base Converter — the free tool I keep coming back to

Binary, octal, decimal and hexadecimal — all at once.

Try it: https://freetoolsgalaxy.com/tools/number-base-converter
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The fastest way is to use a free in-browser number base converter: https://freetoolsgalaxy.com/tools/number-base-converter. Binary, octal, decimal and hexadecimal — all at once.

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It covers the standard mortgage use cases (mortgage, home, loan, payment) and links out to the formula + worked examples if you want to learn the math.

Link: https://freetoolsgalaxy.com/tools/mortgage-calculator

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