The Calendar hole will go live in approximately 13 days. Why not try and solve it ahead of time?
Card Number Validation in all languages in chars. Achievements Cheevos Holes Languages Medals Miscellaneous 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 All Languages ><> 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 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 Bytes Chars Scoring Bytes Chars Language All ><> 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 # Golfer Points Chars Time Submitted 161st jatloe 839 77 10ms 1 Oct 2024 162nd emplv 🇱🇻 839 142 264ms 2 Oct 2024 162nd sean-niemann 🇺🇸 839 142 264ms 2 Oct 2024 164th xsot 🇸🇬 838 57 37ms 6 May 2025 165th Shanethegamer 🇺🇸 838 67 314ms 3 Oct 2024 165th antimon2 🇯🇵 838 67 502ms 9 Oct 2024 167th snoozingnewt 🇨🇦 837 92 96ms 8 hours ago 168th KasperKivimaeki 🇫🇮 837 103 428ms 10 days ago 169th JayXon 🇺🇸 837 109 1,287ms 5 Oct 2024 170th stefangimmillaro 836 68 1,045ms 2 Oct 2024 171st Shanethegamer 🇺🇸 836 77 9ms 1 Oct 2024 171st edsrzf 🇳🇿 836 77 9ms 10 May 2025 171st biocommando 🇫🇮 836 77 9ms 13 Jun 2025 174th xsot 🇸🇬 836 82 2ms 6 May 2025 175th emplv 🇱🇻 836 145 25ms 24 Oct 2024 176th GrayJoKing 🇦🇺 835 47 4ms 1 Oct 2024 177th sean-niemann 🇺🇸 835 114 42ms 2 Oct 2024 178th sean-niemann 🇺🇸 834 81 10ms 20 Dec 2024 179th edsrzf 🇳🇿 834 116 3ms 7 days ago 180th emgordon154 833 69 364ms 18 Nov 2024 181st edsrzf 🇳🇿 833 108 77ms 26 Jul 2025 182nd stefangimmillaro 833 112 145ms 4 Oct 2024 183rd MeWhenI 🇻🇦 833 130 40ms 3 Oct 2024 184th MeWhenI 🇻🇦 833 143 263ms 2 Oct 2024 185th ovs-code 🇩🇪 833 200 447ms 19 Apr 2025 186th stefangimmillaro 832 80 4,333ms 12 Nov 2024 187th JayXon 🇺🇸 832 155 2,650ms 3 Oct 2024 188th qpwoeirut 828 78 10ms 1 Oct 2025 189th m-tkach 🇺🇦 827 138 27ms 3 Oct 2024 190th dcgjb 825 78 9ms 6 May 2025 191st stefangimmillaro 825 99 109ms 3 Oct 2024 192nd retrohun 824 71 9ms 10 Jan 2025 193rd m-tkach 🇺🇦 823 58 55ms 8 Oct 2024 194th ovs-code 🇩🇪 823 78 111ms 2 Oct 2024 195th primo-ppcg 🇹🇭 822 232 525ms 13 Aug 2025 196th albanian-laundromat 821 70 452ms 3 Nov 2025 197th ovs-code 🇩🇪 820 65 5ms 30 Oct 2024 198th albanian-laundromat 820 118 4ms 7 days ago 199th kg583 🇺🇸 820 142 41ms 14 Feb 2025 200th sean-niemann 🇺🇸 818 48 4ms 9 Aug 2025 201st MeWhenI 🇻🇦 818 114 494ms 7 Nov 2025 202nd MeWhenI 🇻🇦 818 183 14ms 2 Oct 2024 203rd MeWhenI 🇻🇦 817 92 10ms 24 Dec 2024 204th MeWhenI 🇻🇦 817 104 18ms 2 Oct 2024 205th canissimia 🇦🇶 817 130 3ms 4 Oct 2024 206th rucin93 🇵🇱 816 71 126ms 17 Dec 2024 207th nwellnhof 🇩🇪 816 84 2ms 2 Oct 2024 207th ovs-code 🇩🇪 816 84 1ms 2 Nov 2024 207th inventshah 816 84 2ms 31 Mar 2025 210th lifthrasiir 🇰🇷 815 197 10ms 19 Dec 2024 211th sisyphus-ppcg 🇦🇺 814 83 9ms 2 Oct 2024 212th MeWhenI 🇻🇦 814 85 2ms 5 Oct 2024 213th MeWhenI 🇻🇦 813 85 101ms 4 Oct 2024 214th ovs-code 🇩🇪 813 106 428ms 1 Oct 2024 214th inventshah 813 106 516ms 1 Oct 2024 216th emgordon154 813 205 464ms 7 Mar 2025 217th Shanethegamer 🇺🇸 812 70 986ms 9 Apr 2025 218th sean-niemann 🇺🇸 811 115 480ms 24 Sep 2025 218th stefangimmillaro 811 115 463ms 6 Oct 2025 220th lifthrasiir 🇰🇷 810 71 370ms 2 Dec 2024 221st kg583 🇺🇸 810 124 7ms 20 Oct 2024 221st AlephSquirrel 810 124 7ms 21 Oct 2024 223rd anter69 🇭🇺 809 59 96ms 11 Oct 2024 223rd Natanaelel 🇸🇪 809 59 49ms 7 Feb 2025 225th edsrzf 🇳🇿 809 137 121ms 86 mins ago 226th stefangimmillaro 808 134 41ms 3 Oct 2024 227th saito-ta 🇯🇵 807 85 1ms 1 Oct 2024 228th stefangimmillaro 807 126 2ms 3 Oct 2024 229th GolfingSuccess 🇬🇷 806 31 66ms 5 Oct 2024 230th emgordon154 805 72 120ms 2 Oct 2024 231st trinityy-7 805 80 10ms 23 Jul 2025 232nd albanian-laundromat 805 148 255ms 15 days ago 233rd error256 804 116 421ms 24 Sep 2025 234th GrayJoKing 🇦🇺 803 58 6ms 24 Oct 2024 235th xsot 🇸🇬 803 125 7ms 20 Oct 2024 236th Shanethegamer 🇺🇸 803 138 142ms 3 Oct 2024 237th DialFrost 🇸🇬 802 106 25ms 23 Mar 2025 238th ovs-code 🇩🇪 802 119 14ms 1 Oct 2024 239th Kacarott 🇦🇺 801 73 1,117ms 1 Oct 2024 239th chunes3 🇺🇸 801 73 1,046ms 2 Oct 2024 First Prev 161–240 of 847 Next Last