The
Calendar
hole will go live in approximately
5 days
. Why not try and solve it ahead of time?
Recent Solutions
Achievements
Cheevos
Golfers
Solutions
All Holes
12 Days of Christmas
24 Game
99 Bottles of Beer
Abundant Numbers
Abundant Numbers (Long)
Arabic to Roman
Arithmetic Numbers
Arrows
Ascending Primes
ASCII Table
Billiards
brainfuck
Card Number Validation
Catalan Numbers
Catalan’s Constant
Christmas Trees
Collatz
CSS Colors
Cubes
Day of Week
DFA Simulator
Diamonds
Divisors
Emirp Numbers
Emirp Numbers (Long)
Emojify
Evil Numbers
Evil Numbers (Long)
Factorial Factorisation
Farey Sequence
Fibonacci
Fizz Buzz
Foo Fizz Buzz Bar
Forsyth–Edwards Notation
Fractions
Game of Life
Gijswijt’s Sequence
Happy Numbers
Happy Numbers (Long)
Hexdump
Hilbert Curve
Intersection
Inventory Sequence
ISBN
Jacobi Symbol
Kaprekar Numbers
Kolakoski Constant
Kolakoski Sequence
Leap Years
Levenshtein Distance
Leyland Numbers
ln 2
Look and Say
Lucky Numbers
Lucky Tickets
Mahjong
Mandelbrot
Maze
Medal Tally
Minesweeper
Morse Decoder
Morse Encoder
Musical Chords
N Queens
Niven Numbers
Niven Numbers (Long)
Number Spiral
Odious Numbers
Odious Numbers (Long)
Ordinal Numbers
PalindromemordnilaP
Pangram Grep
Partition Numbers
Pascal’s Triangle
Pernicious Numbers
Pernicious Numbers (Long)
Poker
Polyominoes
Prime Numbers
Prime Numbers (Long)
Proximity Grid
QR Decoder
Quine
Recamán
Repeating Decimals
Reverse Polish Notation
Reversi
Rijndael S-box
Rock-paper-scissors-Spock-lizard
Roman to Arabic
ROT13
Rule 110
Scrambled Sort
Set
Seven Segment
SI Units
Sierpiński Triangle
Smith Numbers
Spelling Numbers
Star Wars GPT
Star Wars Opening Crawl
Sudoku
Sudoku (Fill-in)
Ten-pin Bowling
Tic-tac-toe
Time Distance
Tongue-twisters
Topological Sort
Tower of Hanoi
Transpose Sentence
Trinomial Triangle
United States
Vampire Numbers
Van Eck Sequence
Zeckendorf Representation
Zodiac Signs
γ
λ
π
τ
φ
√2
𝑒
Apéry’s Constant
Binary Lambda Calculus
Calendar
Connect Four
Continued Fractions
Crossword
CSS Colors (Inverse)
CSS Grid
Ellipse Perimeters
Flags
Floyd-Steinberg Dithering
Gray Code Decoder
Gray Code Encoder
Hexagonal Spiral
Highly Composite Numbers
Multitap Input
NFA Simulator
Numbrix
Odd Polyomino Tiling
p-adic Expansion
Polygon Triangulations
QR Encoder
Quadratic Formula
Semiprime Numbers
Smooth Numbers
Snake
Sphenic Numbers
Taxicab Numbers
Turtle
Tutorial
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><>
Assembly
AWK
Bash
BASIC
Berry
brainfuck
C
C#
C++
Civet
Clojure
COBOL
Coconut
Common Lisp
Crystal
D
Dart
Elixir
Erlang
F#
Factor
Forth
Fortran
Gleam
Go
GolfScript
Groovy
Haskell
Hexagony
J
Janet
Java
JavaScript
jq
Julia
K
Kotlin
Lua
Nim
OCaml
Pascal
Perl
PHP
PowerShell
Prolog
Python
R
Raku
Rockstar
Ruby
Rust
Scheme
sed
SQL
Swift
Tcl
TeX
V
VimL
Wren
Zig
Experimental Language
05AB1E
ALGOL 68
APL
Arturo
Befunge
BQN
CJam
CoffeeScript
Egel
Fennel
Harbour
Hare
Haxe
Hush
Hy
iogii
Knight
Luau
Odin
Picat
Qore
Racket
Rebol
Rexx
Scala
Squirrel
Stax
Uiua
Umka
Vala
Vyxal
Hole
All
12 Days of Christmas
24 Game
99 Bottles of Beer
Abundant Numbers
Abundant Numbers (Long)
Arabic to Roman
Arithmetic Numbers
Arrows
Ascending Primes
ASCII Table
Billiards
brainfuck
Card Number Validation
Catalan Numbers
Catalan’s Constant
Christmas Trees
Collatz
CSS Colors
Cubes
Day of Week
DFA Simulator
Diamonds
Divisors
Emirp Numbers
Emirp Numbers (Long)
Emojify
Evil Numbers
Evil Numbers (Long)
Factorial Factorisation
Farey Sequence
Fibonacci
Fizz Buzz
Foo Fizz Buzz Bar
Forsyth–Edwards Notation
Fractions
Game of Life
Gijswijt’s Sequence
Happy Numbers
Happy Numbers (Long)
Hexdump
Hilbert Curve
Intersection
Inventory Sequence
ISBN
Jacobi Symbol
Kaprekar Numbers
Kolakoski Constant
Kolakoski Sequence
Leap Years
Levenshtein Distance
Leyland Numbers
ln 2
Look and Say
Lucky Numbers
Lucky Tickets
Mahjong
Mandelbrot
Maze
Medal Tally
Minesweeper
Morse Decoder
Morse Encoder
Musical Chords
N Queens
Niven Numbers
Niven Numbers (Long)
Number Spiral
Odious Numbers
Odious Numbers (Long)
Ordinal Numbers
PalindromemordnilaP
Pangram Grep
Partition Numbers
Pascal’s Triangle
Pernicious Numbers
Pernicious Numbers (Long)
Poker
Polyominoes
Prime Numbers
Prime Numbers (Long)
Proximity Grid
QR Decoder
Quine
Recamán
Repeating Decimals
Reverse Polish Notation
Reversi
Rijndael S-box
Rock-paper-scissors-Spock-lizard
Roman to Arabic
ROT13
Rule 110
Scrambled Sort
Set
Seven Segment
SI Units
Sierpiński Triangle
Smith Numbers
Spelling Numbers
Star Wars GPT
Star Wars Opening Crawl
Sudoku
Sudoku (Fill-in)
Ten-pin Bowling
Tic-tac-toe
Time Distance
Tongue-twisters
Topological Sort
Tower of Hanoi
Transpose Sentence
Trinomial Triangle
United States
Vampire Numbers
Van Eck Sequence
Zeckendorf Representation
Zodiac Signs
γ
λ
π
τ
φ
√2
𝑒
Experimental Hole
Apéry’s Constant
Binary Lambda Calculus
Calendar
Connect Four
Continued Fractions
Crossword
CSS Colors (Inverse)
CSS Grid
Ellipse Perimeters
Flags
Floyd-Steinberg Dithering
Gray Code Decoder
Gray Code Encoder
Hexagonal Spiral
Highly Composite Numbers
Multitap Input
NFA Simulator
Numbrix
Odd Polyomino Tiling
p-adic Expansion
Polygon Triangulations
QR Encoder
Quadratic Formula
Semiprime Numbers
Smooth Numbers
Snake
Sphenic Numbers
Taxicab Numbers
Turtle
Tutorial
Hole
Golfer
Bytes
Time
Submitted
Tower of Hanoi
nwellnhof
56
265ms
4 hours ago
Abundant Numbers (Long)
JOrE20
192
426ms
8 hours ago
Emirp Numbers (Long)
JOrE20
1,155
234ms
8 hours ago
Levenshtein Distance
KatieLG
468
3,334ms
10 hours ago
Fibonacci
albanian-laundromat
28
243ms
16 hours ago
Prime Numbers
albanian-laundromat
34
532ms
17 hours ago
Hexagonal Spiral
bitsandbeyond
111
324ms
22 hours ago
Hexdump
IISResetMe
167
305ms
24 hours ago
Reverse Polish Notation
IISResetMe
88
396ms
25 hours ago
Calendar
IISResetMe
161
294ms
25 hours ago
Calendar
JOrE20
1,000
245ms
33 hours ago
Fractions
IISResetMe
82
274ms
45 hours ago
Zeckendorf Representation
JOrE20
125
265ms
2 days ago
Maze
bitsandbeyond
💎
103
4,637ms
3 days ago
12 Days of Christmas
IISResetMe
452
251ms
4 days ago
Fibonacci
DialFrost
🥇
27
244ms
8 days ago
Fibonacci
KasperKivimaeki
44
246ms
8 days ago
Tower of Hanoi
sean-niemann
🥇
51
260ms
8 days ago
Fibonacci
DelaneyJM
35
207ms
9 days ago
γ
JOrE20
1,004
202ms
9 days ago
Tongue-twisters
prestosilver
524
221ms
9 days ago
Tower of Hanoi
gigaprofisi
3,593
172ms
9 days ago
Rijndael S-box
kurkale6ka
780
190ms
10 days ago
Fizz Buzz
mwarvik
96
199ms
10 days ago
Tutorial
kurkale6ka
100
236ms
11 days ago
Prime Numbers
JOrE20
43
247ms
11 days ago
Pernicious Numbers (Long)
DialFrost
🥇
32
253ms
11 days ago
Star Wars Opening Crawl
bitsandbeyond
💎
207
297ms
12 days ago
Leap Years
DialFrost
28
251ms
12 days ago
Vampire Numbers
bitsandbeyond
💎
129
3,941ms
16 days ago
Fibonacci
REOScotte
31
203ms
17 days ago
Tutorial
JOrE20
26
207ms
17 days ago
Gray Code Encoder
JOrE20
37
239ms
17 days ago
Seven Segment
bitsandbeyond
💎
84
257ms
18 days ago
Hilbert Curve
bitsandbeyond
🥈
248
1,383ms
18 days ago
Binary Lambda Calculus
bitsandbeyond
209
756ms
18 days ago
Ellipse Perimeters
bitsandbeyond
67
232ms
18 days ago
Gray Code Decoder
bitsandbeyond
44
1,168ms
18 days ago
Day of Week
KasperKivimaeki
18
224ms
18 days ago
Day of Week
CornerMercury
🥇
16
341ms
19 days ago
Multitap Input
bitsandbeyond
64
273ms
20 days ago
Prime Numbers
okhoel
37
250ms
21 days ago
Tower of Hanoi
Schmitt-Very-Cool
116
268ms
21 days ago
√2
Murphy4444
1,004
221ms
22 days ago
Niven Numbers
snoozingnewt
33
240ms
22 days ago
Ordinal Numbers
Murphy4444
107
287ms
22 days ago
Day of Week
Murphy4444
19
227ms
23 days ago
Foo Fizz Buzz Bar
Murphy4444
82
231ms
23 days ago
Tower of Hanoi
aksyristos
203
256ms
23 days ago
Abundant Numbers
Lv0Sys
55
296ms
23 days ago
Quadratic Formula
bitsandbeyond
436
374ms
23 days ago
Topological Sort
IISResetMe
362
1,293ms
23 days ago
Leap Years
sisyphus-ppcg
🥇
26
331ms
23 days ago
DFA Simulator
IISResetMe
210
695ms
23 days ago
Morse Decoder
IISResetMe
219
257ms
24 days ago
Morse Encoder
IISResetMe
193
258ms
24 days ago
Hilbert Curve
IISResetMe
2,325
204ms
24 days ago
Trinomial Triangle
IISResetMe
87
220ms
24 days ago
Day of Week
CrookedJ
17
221ms
24 days ago
Sudoku
bitsandbeyond
💎
278
1,363ms
24 days ago
Tower of Hanoi
blaztoma
63
248ms
25 days ago
Spelling Numbers
dokutan
778
512ms
25 days ago
Lucky Tickets
dokutan
4,745
257ms
25 days ago
Tower of Hanoi
dokutan
66
253ms
25 days ago
γ
bitsandbeyond
🥉
102
802ms
25 days ago
Tower of Hanoi
pardouin
🥇
51
225ms
25 days ago
PalindromemordnilaP
bitsandbeyond
🥈
64
275ms
25 days ago
Tower of Hanoi
AlephSquirrel
79
248ms
26 days ago
Tower of Hanoi
emgordon154
3,578
210ms
26 days ago
Tower of Hanoi
Yewzir
82
285ms
26 days ago
Tower of Hanoi
HumanoidCPU
88
264ms
26 days ago
Tower of Hanoi
KatieLG
4,093
205ms
26 days ago
Tower of Hanoi
CaedenHarper
81
240ms
26 days ago
Tower of Hanoi
IISResetMe
78
273ms
26 days ago
Set
bitsandbeyond
💎
115
4,873ms
27 days ago
γ
MeWhenI
114
1,315ms
27 days ago
Happy Numbers
snoozingnewt
69
242ms
27 days ago
λ
JOrE20
1,004
208ms
28 Nov 2025
Tower of Hanoi
Msleizak
126
279ms
28 Nov 2025
Card Number Validation
IISResetMe
103
516ms
27 Nov 2025