Hex Addition Table Generator

Generates a configurable NxN addition table (default 0-F) rendered as a real HTML table, with the row headers, column headers, and every cell value all shown in hexadecimal; each cell is computed as row + column in decimal, then hex-formatted. A free online tool from Staaarter, right in your browser.

Runs locallyUpdated 2026-07-26

Overview

Introduction

Hex addition carries at 16 instead of 10, which trips people up the first several times they do it by hand, seeing every sum in a given range laid out at once helps build the right intuition faster than computing sums one at a time.

This tool generates a configurable NxN addition table where the row and column headers and every cell's sum are all shown in hexadecimal.

What Is Hex Addition Table Generator?

An addition table where both axes are labeled with hex digits (0-F by default, extendable to two-digit hex headers for larger sizes) and every cell shows the sum of its row and column header, computed in decimal and converted to hex for display.

It's rendered as a real HTML table (not ASCII art), for the clearest possible two-axis reference grid.

How Hex Addition Table Generator Works

For a table of size N, the headers are the hex representations of 0 through N-1.

Every cell at row r and column c is computed as `r + c` in ordinary decimal arithmetic, then the result is converted to its uppercase hexadecimal string for display.

When To Use Hex Addition Table Generator

Use it as a quick-reference chart while doing hex arithmetic by hand, or while learning where hex addition carries happen.

It's also useful for spot-checking a manually computed hex sum, or for programming and debugging tasks involving hex offsets or address arithmetic.

Features

Advantages

  • Fully deterministic and rendered as a genuine, easy-to-scan table element.
  • Size is configurable from a compact quick-reference chart up to a larger 32x32 table.
  • Makes hex's carry-at-16 behavior visually obvious across a full grid of sums.

Limitations

  • Capped at 32x32 to keep the table a reasonable size to render and read.
  • Cell values beyond a single hex digit show as two-plus hex digits without extra padding.

Examples

A mid-table cell

Input

row A, column 5 (default 0-F table)

Output

F

10 + 5 = 15 in decimal, which is 0xF in hexadecimal.

A carry past a single hex digit

Input

row F, column F (default 0-F table)

Output

1E

15 + 15 = 30 in decimal, which is 0x1E in hexadecimal, a two-digit result even though both inputs were single hex digits.

Best Practices & Notes

Best Practices

  • Stick with the default 0-F size for the most common quick-reference use case; it covers every single-hex-digit sum.
  • Use the table to build intuition for exactly which sums carry into a second hex digit (anything totaling 16 or more).

Developer Notes

Cell values are computed with ordinary JavaScript number addition in decimal (`r + c`), then formatted with `.toString(16).toUpperCase()`; converting to decimal, adding, and converting back is simpler and exactly equivalent to native hex addition for integers in this size range.

Hex Addition Table Generator Use Cases

  • Quick-reference chart while doing hex arithmetic by hand
  • Learning or teaching where hex addition carries happen
  • Spot-checking a manually computed hex sum

Common Mistakes

  • Assuming hex addition carries at 10 like decimal does; it actually carries at 16.
  • Reading a header digit as decimal instead of hex, e.g. treating column "A" as 10 columns further right than it actually is.

Tips

  • Scan along the table's diagonal to see how quickly sums grow past a single hex digit as both row and column increase.
  • Use the default 0-F size unless you specifically need larger, two-digit hex headers.

References

Frequently Asked Questions