Clock: Latest and Earliest Time40 puzzles

Clock: Latest and Earliest Time

A 24-hour digital clock made of matches: move matches between the digits to show the latest or the earliest time possible.

Latest and Earliest Time, One Move

A warm-up: move one match to make the clock show the latest or the earliest time possible. Each puzzle says which.

  1. 1 · No. 48618:59 — Latest Time in 1 Move20 matches · 1 move
  2. 2 · No. 48718:45 — Earliest Time in 1 Move18 matches · 1 move
  3. 3 · No. 48811:27 — Latest Time in 1 Move12 matches · 1 move
  4. 4 · No. 48918:43 — Earliest Time in 1 Move18 matches · 1 move
  5. 5 · No. 49015:28 — Latest Time in 1 Move19 matches · 1 move
  6. 6 · No. 49118:36 — Earliest Time in 1 Move20 matches · 1 move
  7. 7 · No. 49218:33 — Latest Time in 1 Move19 matches · 1 move
  8. 8 · No. 49317:26 — Earliest Time in 1 Move16 matches · 1 move

Latest Time, Two Moves

Move two matches to make the latest time possible. A 9 is not always best: the hours stop at 23 and the minutes at 59.

  1. 1 · No. 49420:09 — Latest Time in 2 Moves23 matches · 2 moves
  2. 2 · No. 49518:58 — Latest Time in 2 Moves21 matches · 2 moves
  3. 3 · No. 49623:09 — Latest Time in 2 Moves22 matches · 2 moves
  4. 4 · No. 49723:47 — Latest Time in 2 Moves17 matches · 2 moves
  5. 5 · No. 49814:42 — Latest Time in 2 Moves15 matches · 2 moves
  6. 6 · No. 49918:18 — Latest Time in 2 Moves18 matches · 2 moves
  7. 7 · No. 50011:41 — Latest Time in 2 Moves10 matches · 2 moves
  8. 8 · No. 50103:19 — Latest Time in 2 Moves19 matches · 2 moves

Earliest Time, Two Moves

Move two matches to make the earliest time possible. Leading zeros are fine on a clock: 00:00 is the earliest time of day.

  1. 1 · No. 50214:18 — Earliest Time in 2 Moves15 matches · 2 moves
  2. 2 · No. 50322:47 — Earliest Time in 2 Moves17 matches · 2 moves
  3. 3 · No. 50422:42 — Earliest Time in 2 Moves19 matches · 2 moves
  4. 4 · No. 50508:18 — Earliest Time in 2 Moves22 matches · 2 moves
  5. 5 · No. 50614:53 — Earliest Time in 2 Moves16 matches · 2 moves
  6. 6 · No. 50717:18 — Earliest Time in 2 Moves14 matches · 2 moves
  7. 7 · No. 50823:29 — Earliest Time in 2 Moves21 matches · 2 moves
  8. 8 · No. 50917:42 — Earliest Time in 2 Moves14 matches · 2 moves

Latest Time, Three Moves

The hardest latest-time puzzles: move three matches. Taking the latest time after every move won’t get you there.

  1. 1 · No. 51021:03 — Latest Time in 3 Moves18 matches · 3 moves
  2. 2 · No. 51113:44 — Latest Time in 3 Moves15 matches · 3 moves
  3. 3 · No. 51220:29 — Latest Time in 3 Moves22 matches · 3 moves
  4. 4 · No. 51316:14 — Latest Time in 3 Moves14 matches · 3 moves
  5. 5 · No. 51407:17 — Latest Time in 3 Moves14 matches · 3 moves
  6. 6 · No. 51521:49 — Latest Time in 3 Moves17 matches · 3 moves
  7. 7 · No. 51620:17 — Latest Time in 3 Moves16 matches · 3 moves
  8. 8 · No. 51706:16 — Latest Time in 3 Moves20 matches · 3 moves

Earliest Time, Three Moves

The hardest earliest-time puzzles: move three matches. Taking the earliest time after every move won’t get you there.

  1. 1 · No. 51820:24 — Earliest Time in 3 Moves20 matches · 3 moves
  2. 2 · No. 51914:51 — Earliest Time in 3 Moves13 matches · 3 moves
  3. 3 · No. 52020:20 — Earliest Time in 3 Moves22 matches · 3 moves
  4. 4 · No. 52113:04 — Earliest Time in 3 Moves17 matches · 3 moves
  5. 5 · No. 52215:33 — Earliest Time in 3 Moves17 matches · 3 moves
  6. 6 · No. 52313:30 — Earliest Time in 3 Moves18 matches · 3 moves
  7. 7 · No. 52420:40 — Earliest Time in 3 Moves21 matches · 3 moves
  8. 8 · No. 52513:23 — Earliest Time in 3 Moves17 matches · 3 moves