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 bytes. 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 Bytes Time Submitted 241st edsrzf 🇳🇿 809 137 121ms 55 mins ago 242nd kg583 🇺🇸 808 82 444ms 1 Oct 2024 242nd sean-niemann 🇺🇸 808 82 373ms 23 Dec 2024 244th stefangimmillaro 808 134 41ms 3 Oct 2024 245th stefangimmillaro 807 126 2ms 3 Oct 2024 246th GolfingSuccess 🇬🇷 806 31 66ms 5 Oct 2024 247th trinityy-7 805 80 10ms 23 Jul 2025 248th SirBogman 🇺🇸 805 99 16ms 8 Oct 2024 249th albanian-laundromat 805 148 255ms 15 days ago 250th error256 804 116 421ms 24 Sep 2025 251st GrayJoKing 🇦🇺 803 58 6ms 24 Oct 2024 252nd xsot 🇸🇬 803 125 7ms 20 Oct 2024 253rd Shanethegamer 🇺🇸 803 138 142ms 3 Oct 2024 254th antimon2 🇯🇵 802 70 585ms 9 Oct 2024 255th DialFrost 🇸🇬 802 106 25ms 23 Mar 2025 256th ovs-code 🇩🇪 802 119 14ms 1 Oct 2024 257th Kacarott 🇦🇺 801 73 1,117ms 1 Oct 2024 257th chunes3 🇺🇸 801 73 1,046ms 2 Oct 2024 259th MeWhenI 🇻🇦 801 127 2ms 5 Oct 2024 259th albanian-laundromat 801 127 3ms 3 Nov 2025 261st Shanethegamer 🇺🇸 801 208 1,488ms 14 Apr 2025 261st DialFrost 🇸🇬 801 208 521ms 18 Apr 2025 263rd stefangimmillaro 800 89 417ms 4 Oct 2024 264th MeWhenI 🇻🇦 799 88 1ms 2 Oct 2024 265th sean-niemann 🇺🇸 799 92 112ms 1 Oct 2025 266th duckyluuk 🇳🇱 798 83 362ms 3 Oct 2024 266th emgordon154 798 83 440ms 18 Nov 2024 268th albanian-laundromat 797 74 765ms 3 Nov 2025 269th anter69 🇭🇺 797 100 16ms 1 Oct 2024 269th bzijlema 🇳🇱 797 100 16ms 10 Oct 2024 269th bricknellj 797 100 16ms 4 Mar 2025 272nd edsrzf 🇳🇿 797 117 437ms 24 Sep 2025 273rd 2bular 796 49 31ms 8 Nov 2025 274th tayloia 🇬🇧 795 81 9ms 3 Oct 2024 274th targrik 795 81 9ms 8 Feb 2025 274th Lv0Sys 🇵🇱 795 81 10ms 8 days ago 277th DialFrost 🇸🇬 795 85 6ms 1 Oct 2024 277th xsot 🇸🇬 795 85 5ms 7 Oct 2024 279th stefangimmillaro 794 87 99ms 4 Oct 2024 280th Shanethegamer 🇺🇸 794 102 384ms 4 Oct 2024 281st Shanethegamer 🇺🇸 794 128 2ms 3 Oct 2024 282nd kg583 🇺🇸 794 160 43ms 13 Feb 2025 282nd CLOStrophobic 🇮🇹 794 160 40ms 27 Feb 2025 284th DialFrost 🇸🇬 793 84 4,106ms 26 Oct 2024 285th albanian-laundromat 793 120 42ms 3 Nov 2025 286th MeWhenI 🇻🇦 791 90 435ms 2 Oct 2024 287th MeWhenI 🇻🇦 791 109 394ms 2 Oct 2024 288th jared-hughes 791 203 101ms 20 Dec 2024 289th saito-ta 🇯🇵 790 74 7ms 1 Oct 2024 290th pardouin 🇫🇷 789 81 131ms 29 Jan 2025 290th ovs-code 🇩🇪 789 81 122ms 17 Apr 2025 292nd ovs-code 🇩🇪 789 84 372ms 3 Oct 2024 292nd Shanethegamer 🇺🇸 789 84 381ms 3 Oct 2024 294th lifthrasiir 🇰🇷 789 101 16ms 21 Nov 2024 294th btjones0 789 101 16ms 2 Dec 2024 296th emgordon154 789 151 262ms 17 Jan 2025 297th Natanaelel 🇸🇪 788 48 212ms 1 Oct 2024 298th KingSkyrock 🇺🇸 785 82 9ms 14 Oct 2024 299th Shanethegamer 🇺🇸 785 88 99ms 4 Oct 2024 300th kg583 🇺🇸 785 94 4ms 13 Nov 2025 301st SirBogman 🇺🇸 785 138 39ms 11 Jul 2025 302nd edsrzf 🇳🇿 784 119 152ms 23 Jul 2025 302nd namelessiw 784 119 440ms 9 Oct 2025 304th Shanethegamer 🇺🇸 784 152 264ms 3 Oct 2024 304th targrik 784 152 264ms 7 Jul 2025 306th stefangimmillaro 783 61 33ms 1 Oct 2024 307th Shanethegamer 🇺🇸 782 91 416ms 3 Oct 2024 308th annaproxy 781 102 16ms 1 Oct 2024 308th snoozingnewt 🇨🇦 781 102 9ms 12 days ago 310th SirBogman 🇺🇸 780 50 34ms 8 Jul 2025 311th ovs-code 🇩🇪 780 75 1,104ms 1 Oct 2024 312th MeWhenI 🇻🇦 780 122 39ms 5 Oct 2024 313th GrayJoKing 🇦🇺 779 82 127ms 1 Oct 2024 314th sean-niemann 🇺🇸 779 107 332ms 3 Oct 2024 315th adriweb 🇫🇷 777 102 2ms 5 Oct 2024 316th Shanethegamer 🇺🇸 777 120 454ms 24 Sep 2025 317th emgordon154 777 166 1,626ms 2 Oct 2024 318th DialFrost 🇸🇬 776 76 745ms 30 Aug 2025 319th m-tkach 🇺🇦 776 131 3ms 4 Oct 2024 320th uttumuttu 🇫🇮 775 83 9ms 1 Oct 2024 First Prev 241–320 of 850 Next Last