ASCII Table
Computing
All 128 ASCII characters with their decimal, hexadecimal, octal and binary codes — control characters, digits, letters and punctuation in one table.
128 rows
Reference Tables
Complete lookup tables for maths, computing, units and notation — every row computed rather than transcribed, with search, charts and sources.
Tables
10
Rows in total
648
Categories
4
Languages
EN · DE
Every table
10 of 10 tables
Why these tables are correct
Computed, not transcribed
A lookup table is only as good as its worst row. That is why almost nothing here is entered by hand: the hex, octal and binary columns of the ASCII table come from the code point itself, the 400 products of the times table from a multiplication, the primes from a sieve, the powers of two from BigInt so that every digit above 2⁵³ is still exact.
Where values do come from a source — the SI prefixes from the SI Brochure, the physical constants from CODATA — the source is on the page with a link and a verification date. And where a value is measured rather than defined, you see its uncertainty instead of a deceptively exact number.
Frequently asked questions
What will you find here?
Ten complete lookup tables from maths, computing, units and notation — from all 128 ASCII codes through the 24 SI prefixes to the 168 primes below 1,000. Each table sits complete on one page, with a search box, charts and sources.
How reliable are the values?
Almost every cell is computed when the page is built rather than typed in: the ASCII columns come from the code point, the primes from a sieve of Eratosthenes, the powers of two from BigInt. Where values do come from a source — SI prefixes, physical constants — it is linked and carries a verification date.
Can I search inside a table?
Yes. Every table has a search box that matches across all columns at once. In the ASCII table the same row turns up for “65”, “41” or “A” — decimal, hex and character all lead to the same hit.
Can the tables be printed?
Yes. The tables ship complete in the page source rather than loading in afterwards, so your browser's print command captures every row — including the ones currently scrolled out of view.
How do these pages differ from the converters?
A converter answers one question with your numbers. A reference table shows the whole range at once — useful when you want to spot a pattern, estimate a value, or look something up without knowing exactly what you are after.
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