burger fun / Four Fours / Solver
Make 2 with four 4s
The classic four fours puzzle: build an expression from exactly four 4s that equals 2. 2 can be made with nothing but four 4s, + - × ÷, and parentheses.
Solutions using only + - × ÷
4 / 4 + 4 / 4 = 24 × 4 / (4 + 4) = 24 - (4 + 4) / 4 = 24 / ((4 + 4) / 4) = 2
Solutions with concatenation and decimals
4 / .4 - 4 - 4 = 2.4 / .4 + 4 / 4 = 24 - .4 × 4 - .4 = 24 - .4 - .4 × 4 = 2.4 × (4 + 4 / 4) = 2
…and 11 more at this tier.
Solutions with square roots, factorials, exponents
4 + 4 - 4! / 4 = 2(4 + 44) / 4! = 24! / 4! + 4 / 4 = 2(4! - 4 × 4) / 4 = 2(4 - 4)! + 4 / 4 = 2
…and 6878 more at this tier.
6903 distinct solutions found in total, after removing trivial rearrangements.
How 2 compares
2 has 6,903 distinct solutions across all three tiers — #3 most plentiful of the 95 solvable targets. 4 of them use nothing but + - × ÷. Next door, 1 has 7,445 solutions and 3 has 1,012 solutions. The nearest impossible target is 73, 71 away — proven unreachable, not just unsolved.
If 2 went down easily, make 3 with four 4s — 1,012 solutions, the nearest step up in scarcity.
Make 1 with four 4s · Make 3 with four 4s
The Number Lab
Same idea, different constraints: four 9s, four 4s, or any four digits you like.
- Four Nines — the daily puzzle
- Four Nines solver — every target, solved
- Four Fours — the 1881 original
- Four Fours solver — including the impossible five
- Make 24 solver — any four digits
- Today's 24 — one new hand a day
Got what you came for?
Stay for something you did not search for.
- Four Nines — the daily sibling: four 9s, one target, new at midnight
- The Reflex Lab — nine ways to measure your hands and memory, none of them polite about it
- hand me something weird — a random pick from the directory. Could be the horse.
Read up on the 1881 original, pick another number in the solver, or find more free math games.