The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 2 days. Why not try and solve them ahead of time?
Ordinal Numbers 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 Calendar Card Number Validation Catalan Numbers Catalan’s Constant Christmas Trees Collatz Continued Fractions 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 Multitap Input 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 Alphabetic Numbers Apéry’s Constant Binary Lambda Calculus Connect Four Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Rectangle Fill Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial All Languages ><> ALGOL 68 ArkScript 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 APL Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight Lily Luau Odin Picat Qore Racket Rebol Rexx Scala Squirrel Stax Uiua Umka Vala Vyxal Bytes Chars Scoring Bytes Chars Language All ><> ALGOL 68 ArkScript 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 APL Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight Lily 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 Calendar Card Number Validation Catalan Numbers Catalan’s Constant Christmas Trees Collatz Continued Fractions 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 Multitap Input 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 Alphabetic Numbers Apéry’s Constant Binary Lambda Calculus Connect Four Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Rectangle Fill Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial # Golfer Points Chars Time Submitted 801st DialFrost 🇸🇬 741 43 3ms 3 Feb 2024 801st bstrat 741 43 3ms 13 Sep 2024 801st lifthrasiir 🇰🇷 741 43 3ms 29 Nov 2024 804th DialFrost 🇸🇬 741 77 389ms 16 Jan 2024 804th rucin93 🇵🇱 741 77 507ms 16 Jan 2024 804th m-tkach 🇺🇦 741 77 428ms 20 Jan 2024 807th janbehrens 🇩🇪 741 85 238ms 5 Dec 2023 808th raphaelimahorn 740 86 14ms 13 Aug 2020 808th vphoebe 740 86 11ms 26 May 2022 808th olleicua 🇺🇸 740 86 12ms 13 Jan 2024 808th xyangst 740 86 13ms 7 Oct 2024 808th Salutations45 740 86 12ms 11 Nov 2024 813th jared-hughes 740 98 2ms 17 Jul 2022 814th m-tkach 🇺🇦 740 125 448ms 23 Aug 2022 815th lynn 739 124 16ms 9 Dec 2021 816th GrayJoKing 🇦🇺 737 79 156ms 4 Aug 2024 817th HumanoidCPU 737 86 13ms 18 Feb 2025 818th xAlien95 736 122 110ms 16 Jul 2020 819th MeWhenI 🇻🇦 735 34 59ms 25 Aug 2022 820th KatieLG 🇬🇧 735 60 38ms 2 Oct 2025 821st Attero 🇸🇪 735 81 10ms 25 Sep 2023 822nd primo-ppcg 🇹🇭 735 102 200ms 25 Dec 2020 823rd Shanethegamer 🇺🇸 735 124 38ms 28 Jun 2022 824th postie77 734 111 397ms 26 May 2023 824th janbehrens 🇩🇪 734 111 382ms 5 Dec 2023 824th Shanethegamer 🇺🇸 734 111 396ms 26 Mar 2024 824th pardouin 🇫🇷 734 111 436ms 26 Oct 2024 828th Aurel300 🇨🇭 734 148 166ms 6 Jun 2024 828th The3gs 734 148 174ms 29 Nov 2024 830th cbrt-x 734 154 179ms 10 Oct 2023 830th YAJUE114514 734 154 177ms 16 Aug 2025 832nd kkoenig 734 168 288ms 13 Sep 2024 833rd MeWhenI 🇻🇦 734 209 1,762ms 7 Nov 2025 834th MeWhenI 🇻🇦 733 86 227ms 15 Feb 2023 835th Lv0Sys 🇵🇱 733 99 2ms 3 Dec 2025 836th GolfingSuccess 🇬🇷 733 199 36ms 15 Mar 2023 837th Shanethegamer 🇺🇸 732 51 3ms 26 Apr 2023 838th jackkav 732 87 11ms 24 Oct 2019 838th jake-freeman 732 87 12ms 27 May 2020 840th SirBogman 🇺🇸 731 78 407ms 16 Jan 2024 840th sisyphus-ppcg 🇦🇺 731 78 437ms 17 Jan 2024 840th JunkIce 731 78 440ms 3 Dec 2024 840th GolfingSuccess 🇬🇷 731 78 379ms 5 Feb 2026 840th CaedenHarper 🇨🇦 731 78 398ms 8 Feb 2026 845th GrayJoKing 🇦🇺 731 90 12ms 7 Apr 2021 846th HumanoidCPU 730 123 117ms 21 Mar 2024 847th Shanethegamer 🇺🇸 729 76 4ms 13 Aug 2024 847th GolfingSuccess 🇬🇷 729 76 6ms 16 Aug 2024 849th daedals 729 87 13ms 25 Jul 2019 849th hoodadam 729 87 12ms 30 Aug 2019 849th sk- 729 87 13ms 11 Sep 2019 849th sisyphus-ppcg 🇦🇺 729 87 12ms 1 Nov 2020 849th inventshah 729 87 12ms 10 May 2021 849th Sp3000 🇦🇺 729 87 13ms 23 May 2021 849th enbyte 729 87 12ms 7 Jun 2021 849th lovernj 729 87 13ms 21 Jan 2022 849th Bonjour27891 🇻🇳 729 87 13ms 9 Feb 2022 849th jared-hughes 729 87 11ms 9 Feb 2022 849th primo-ppcg 🇹🇭 729 87 12ms 13 Feb 2022 849th lynn 729 87 12ms 13 Feb 2022 849th stefangimmillaro 729 87 12ms 17 May 2022 849th Seek64 🇩🇪 729 87 12ms 2 Jun 2022 849th nwellnhof 🇩🇪 729 87 12ms 2 Jun 2022 849th Eilonlif 🇮🇱 729 87 13ms 11 Sep 2022 849th Alex-x90 🇺🇸 729 87 12ms 18 Feb 2023 849th InigoK 🇺🇸 729 87 12ms 10 Jun 2023 849th bizy-coder 729 87 13ms 22 Jul 2023 849th minhtrancccp 729 87 12ms 27 Sep 2023 849th stertooy 🇧🇪 729 87 12ms 14 Jun 2024 849th croc54 729 87 12ms 15 Dec 2024 849th kops-cg 729 87 13ms 14 Feb 2025 849th andrewjc2000 729 87 13ms 6 Mar 2025 849th 4atj 729 87 13ms 30 Jun 2025 849th blaztoma 🇱🇹 729 87 12ms 3 Oct 2025 849th ryyyn 🇺🇸 729 87 12ms 2 Nov 2025 849th sunleonid 729 87 13ms 10 Jan 2026 849th souta-1326 729 87 13ms 19 Feb 2026 849th bzijlema 🇳🇱 729 87 13ms 24 Feb 2026 879th albanian-laundromat 729 125 43ms 19 Aug 2025 880th mousetail 🇳🇱 729 149 141ms 22 Dec 2022 First Prev 801–880 of 1,895 Next Last