Quick start

1. Press a Try a sample button in the header to load a worked example, or start from scratch.
2. Set each letter's min/max value and whether its value must be unique in the Constraints grid.
3. Type one expression per line in the Expressions box (e.g. SEND+MORE==MONEY).
4. Press Analyze. Solutions stream into the Output panel as they are found.

On this page

• The constraints grid
• Uniqueness
• Allowed-value lists
• Writing expressions
• Operators
• Alphametic words
• Math functions
• Output & controls
• Tips

The constraints grid

Each usable letter — the Latin letters A–Z followed by the Greek letters α β γ δ ε ζ η θ κ λ ξ ρ σ τ ψ ω — has a row with three controls:

Control	Meaning
Checkbox (left of the letter)	Whether this letter's value must be unique among the other ticked letters.
First number box	The minimum value the letter can take (default 0).
Second number box	The maximum value (default 9) — or a comma-separated list of the exact values allowed.

A letter you don't use in any expression is simply ignored, so you only need to set ranges for letters that appear.

Uniqueness

Tick a letter's checkbox to require it to hold a value different from every other ticked letter. This is what makes a classic alphametic work: in SEND + MORE = MONEY every letter stands for a different digit, so all the participating letters are ticked.

• Toggle Uniqueness flips every letter's checkbox at once — a fast way to turn the whole alphabet unique (then untick any exceptions).
• Each expression's variable values are unique (the checkbox below the grid) is a different, looser rule: it requires the letters within a single expression to differ from each other, without forcing global uniqueness. Useful for grid puzzles where each equation's terms must be distinct but values may repeat across equations.

Allowed-value lists

Instead of a single maximum, the max box accepts a comma-separated list of the only values the letter may take, e.g. 2,4,6,8 to restrict it to even digits.

Important: the search still starts a letter at its min value, so set the min to the lowest value in your list (e.g. min 2 for a list of 2,4,6,8). Otherwise the min value leaks in as an extra, unwanted candidate.

Writing expressions

Enter one expression per line. Each line is a relationship that a valid solution must satisfy. Two shapes are common:

• Assignment / equality: D = E or A == B*D*G — the two sides must be equal.
• Inequality: A > B, D > I + 10 — a comparison that must hold.

A single = is treated the same as == (equality), so you can write equations naturally. Whitespace is ignored.

Operators

Operator	Meaning
= / ==	Equal to
!=	Not equal to
>   <	Greater than / less than
>=   <=	Greater/less than or equal to
+ - * /	Arithmetic
^	Power (e.g. I ^ 2)
%	Modulo / remainder (e.g. D % 10 == 9)
( )	Grouping

Alphametic words

A run of two or more capital Latin letters is read as a multi-digit number, with each letter a digit and the leftmost the most significant. So SEND is expanded to S·1000 + E·100 + N·10 + D automatically. That is what lets you write SEND+MORE==MONEY directly instead of spelling out the place values.

This expansion applies only to capital-letter runs. Greek letters are always single variables, so use them when you want plain one-digit unknowns rather than word digits.

For genuine alphametics, give each leading letter a min of 1 so a number doesn't start with a zero (e.g. in SEND+MORE=MONEY, set S and M to min 1).

Math functions

Expressions are evaluated with the math.js engine, so its functions are available — for example:

• floor(x), ceil(x), round(x) — rounding
• sqrt(x), abs(x), x ^ y — roots and powers
• x % y — remainder

Example: A = floor(C / D), I = sqrt(C).

Output & controls

• Analyze — runs the search. Solutions appear in the Output panel as A=…;B=…;… lines, one per solution, ending with Finished! (or No solutions found!). The search stops after 100 solutions.
• Clear — empties the input, output and all constraints.
• Time spent — how many seconds the current search has taken; large unconstrained puzzles can take a while, so tighten ranges to speed them up.
• The search runs in a background worker, so the page stays responsive and partial progress is shown while it works.

Tips

• Narrow the ranges. The search tries every combination, so every letter you pin down (a tighter min/max or an allowed-value list) makes it dramatically faster.
• Add the obvious constraints. Inequalities and leading-digit minimums prune huge parts of the search space.
• Start from a sample. The four header samples cover the common shapes — a chained-arithmetic puzzle, a classic alphametic, a functions puzzle, and a large unique-value sum grid — and are a good template to edit.

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