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 321st albanian-laundromat 763 118 77ms 13 Nov 2025 322nd GolfingSuccess 🇬🇷 762 70 6ms 6 Jun 2025 323rd Shanethegamer 🇺🇸 761 132 7ms 2 Oct 2024 324th inventshah 760 85 18ms 4 Oct 2024 324th Artemis21 🇬🇧 760 85 10ms 10 Jan 2025 324th keelimeguy 🇺🇸 760 85 15ms 14 Jun 2025 327th MeWhenI 🇻🇦 759 89 5ms 2 Oct 2024 328th emgordon154 758 63 40ms 18 Nov 2024 328th SirBogman 🇺🇸 758 63 33ms 19 Jul 2025 330th weliveinhell 🇭🇹 757 85 9ms 1 Oct 2024 330th SteRoy 757 85 9ms 13 May 2025 332nd AlephSquirrel 756 76 447ms 1 Oct 2024 333rd 0xjac 🇨🇭 754 158 256ms 17 Jun 2025 334th GrayJoKing 🇦🇺 751 90 4ms 1 Oct 2024 335th stackofbears 750 52 35ms 14 Mar 2025 336th DialFrost 🇸🇬 749 75 1,019ms 10 Oct 2024 337th MeWhenI 🇻🇦 749 162 26ms 2 Oct 2024 338th Maznek 748 86 10ms 4 Oct 2024 339th MeWhenI 🇻🇦 748 89 4,060ms 24 Oct 2024 340th MeWhenI 🇻🇦 748 106 1ms 2 Oct 2024 341st rak1507 🇬🇧 747 38 2ms 30 Dec 2024 342nd Babafaba 747 77 366ms 11 Nov 2025 343rd Shanethegamer 🇺🇸 746 64 53ms 3 Oct 2024 343rd Andriamanitra 🇫🇮 746 64 41ms 5 Oct 2024 345th luuumine 🇫🇷 745 92 1ms 13 days ago 345th bzd7 745 92 2ms 11 days ago 347th Shanethegamer 🇺🇸 744 121 83ms 3 Oct 2024 348th sean-niemann 🇺🇸 743 93 101ms 24 Oct 2024 349th sean-niemann 🇺🇸 743 116 469ms 24 Oct 2024 349th luuumine 🇫🇷 743 116 517ms 3 days ago 351st SirBogman 🇺🇸 741 63 278ms 23 Jul 2025 352nd GrayJoKing 🇦🇺 740 79 1,204ms 1 Oct 2024 353rd KrausRaus 🇺🇸 740 87 9ms 1 Oct 2024 353rd GeorgeStechman 🇬🇧 740 87 9ms 24 Oct 2024 353rd coreynash 740 87 9ms 13 Feb 2025 353rd kirjavascript 740 87 9ms 22 Jul 2025 357th Shanethegamer 🇺🇸 740 90 3,803ms 28 Oct 2024 357th ScottHamper 740 90 2,700ms 7 days ago 359th HumanoidCPU 737 78 414ms 7 Mar 2025 360th sean-niemann 🇺🇸 737 93 3ms 24 Oct 2024 361st MeWhenI 🇻🇦 736 111 117ms 2 Oct 2024 362nd MeWhenI 🇻🇦 735 34 64ms 2 Oct 2024 362nd emgordon154 735 34 63ms 11 Sep 2025 364th stefangimmillaro 735 92 9ms 2 Oct 2024 364th Shanethegamer 🇺🇸 735 92 5ms 3 Oct 2024 366th Shanethegamer 🇺🇸 735 100 116ms 24 May 2025 367th wh3n3v3r 🇨🇿 734 88 10ms 18 Nov 2024 368th Shanethegamer 🇺🇸 733 116 18ms 1 Oct 2024 369th Shanethegamer 🇺🇸 732 156 30ms 2 Oct 2024 370th Shanethegamer 🇺🇸 731 101 4ms 2 Oct 2024 371st error256 731 109 8ms 24 Jul 2025 372nd stefangimmillaro 731 114 326ms 13 Oct 2024 373rd anter69 🇭🇺 729 78 1,023ms 1 Oct 2024 374th stefangimmillaro 729 94 1ms 30 Oct 2024 375th Shanethegamer 🇺🇸 729 112 106ms 3 Oct 2024 376th CLOStrophobic 🇮🇹 728 160 40ms 27 Feb 2025 377th zacjl 724 110 6ms 10 Oct 2024 378th Shanethegamer 🇺🇸 724 126 1,275ms 2 Oct 2024 379th dtbao20 🇻🇳 723 89 10ms 1 Oct 2024 379th madeforlosers 723 89 8ms 17 Oct 2024 379th junkondo-jp 723 89 9ms 14 Dec 2024 382nd annaproxy 723 132 14ms 1 Oct 2024 383rd MeWhenI 🇻🇦 721 179 1,697ms 7 Nov 2025 384th weeble 720 74 6ms 1 Jul 2025 385th MeWhenI 🇻🇦 720 78 416ms 2 Oct 2024 386th Shanethegamer 🇺🇸 720 96 2ms 3 Oct 2024 387th nwellnhof 🇩🇪 718 90 18ms 1 Oct 2024 387th ovs-code 🇩🇪 718 90 15ms 3 Oct 2024 387th ryyyn 🇺🇸 718 90 19ms 26 Jul 2025 387th luuumine 🇫🇷 718 90 16ms 8 Oct 2025 387th JOrE20 🇺🇸 718 90 18ms 17 days ago 392nd ovs-code 🇩🇪 716 81 122ms 17 Apr 2025 393rd alexsave 715 90 9ms 28 Oct 2024 394th snyderek 🇺🇸 712 121 53ms 1 Oct 2024 395th h3ra993huskp 🇯🇵 712 131 497ms 18 days ago 396th rzv-me 711 95 5ms 5 Oct 2024 397th 5cw 🇺🇸 710 91 17ms 1 Oct 2024 397th stefangimmillaro 710 91 16ms 13 Oct 2024 397th dokutan 710 91 10ms 19 Oct 2024 397th GrayJoKing 🇦🇺 710 91 18ms 2 Jul 2025 First Prev 321–400 of 846 Next Last