Aisha K.
Mar 12, 2026
Clean layout and the results update instantly. Exactly what I needed for a quick planning check.
Unit Converters
Base Conversion: Binary, Decimal, Hex, Octal
n = parse(value, fromBase); output = n.toString(toBase).
parseInt in one base, toString in another, 2–36. FF₁₆ is 255₁₀ is 11111111₂. Fractional nibbles and two’s-complement word size are not in the box. Leading zeros are dropped.
Bases 2–36
Base 10
255
Not two’s-complement.
Plain-English guide
Terms & how it works
Confused by a field? Read the short definitions here while you use the tool.
Value
The “Value” value used in this tool’s formula. Adjust it to see results update live.
From base
The “From base” value used in this tool’s formula. Adjust it to see results update live.
To base
The “To base” value used in this tool’s formula. Adjust it to see results update live.
How this calculator works
parseInt in one base, toString in another, 2–36. FF₁₆ is 255₁₀ is 11111111₂. Fractional nibbles and two’s-complement word size are not in the box. Leading zeros are dropped. n = parse(value, fromBase); output = n.toString(toBase). Example: FF hex → 255 decimal → 377 octal → 11111111 binary.
n = parse(value, fromBase); output = n.toString(toBase).
Example: FF hex → 255 decimal → 377 octal → 11111111 binary.
When to use this Number Base
Common use cases
- parseInt in one base, toString in another, 2–36. FF₁₆ is 255₁₀ is 11111111₂. Fractional nibbles and two’s-complement word size are not in the box. Leading zeros are dropped.
- Sanity-check with this case: FF hex → 255 decimal → 377 octal → 11111111 binary.
- The relationship is: n = parse(value, fromBase); output = n.toString(toBase).
Localized examples
- Unit Converters: the example on this page uses the same formula as the widget.
What you get
- Fields: Value, From base, To base
- n = parse(value, fromBase); output = n.toString(toBase).
- Example on the page: FF hex → 255 decimal → 377 octal → 11111111 binary.
How to Convert Number Base Step-by-Step
- 1Enter Value, From base, To base. Use the values you have, not a catalog average, unless that is all you know.
- 2n = parse(value, fromBase); output = n.toString(toBase).
- 3Worked case: FF hex → 255 decimal → 377 octal → 11111111 binary.
- 4Check which dictionary the other person is using — US or UK, decimal or 1,024 — then trust the number.
Governing formula
n = parse(value, fromBase); output = n.toString(toBase).
FF hex → 255 decimal → 377 octal → 11111111 binary.
Example: set Value = 16, From base = 16, To base = 10, then read the result.
Variable definitions
- value
Value
The “Value” field. Default 16; typical range 2–36.
- fromBase
From base
The “From base” field. Default 16; typical range 2–36.
- toBase
To base
The “To base” field. Default 10; typical range 2–36.
- The conversion (n = parse(value, fromBase); output = n.toString(toBase).) does not pick US vs UK gallons, SI vs binary megabytes, or Mach at altitude for you. Read the footnote on the page.
- Nothing here is uploaded for the calculation itself.
Frequently Asked Questions
Not a positional system we support. Stay 2–36.
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Community
Reviews & Ratings
See what others think about this tool, then leave your own rating to help improve CalculioHub.
4.8
out of 5.0
4 reviews
Daniel R.
Feb 28, 2026
Very usable on mobile. Would love a save/export option later, but the math feels solid.
Priya S.
Feb 3, 2026
The FAQ section answered my questions before I even had to search. Smooth dark mode too.
Marcus L.
Jan 19, 2026
Simple inputs, clear outputs. This replaced three bookmarks I used to juggle.
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