burger fun / Four Nines / Solver
Make 2 with four 9s
The classic four nines puzzle: build an expression from exactly four 9s that equals 2. 2 can be made with nothing but four 9s, + - × ÷, and parentheses.
Solutions using only + - × ÷
9 / 9 + 9 / 9 = 2
Solutions with concatenation and decimals
99 / 9 - 9 = 2.9 + 9.9 / 9 = 29.9 / .9 - 9 = 2.9 + .99 / .9 = 2.9 / .9 + 9 / 9 = 2
…and 3 more at this tier.
Solutions with square roots, factorials, exponents
9! / 9! + 9 / 9 = 2(9 - 9)! + 9 / 9 = 2.9 / .9 + 9! / 9! = 29! / 9! + 9! / 9! = 2(.9 - .9)! + 9 / 9 = 2
…and 2087 more at this tier.
2101 distinct solutions found in total, after removing trivial rearrangements.
How 2 compares
2 has 2,101 distinct solutions across all three tiers — #6 most plentiful of all 100 targets. Exactly one of them uses nothing but + - × ÷. Next door, 1 has 13,973 solutions and 3 has 6,307 solutions.
If 2 went down easily, make 4 with four 9s — 722 solutions, the nearest step up in scarcity.
Make 1 with four 9s · Make 3 with four 9s
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 puzzle: 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.
Play the daily Four Nines puzzle, pick another number in the solver, or find more free math games.