The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 3 days. Why not try and solve them ahead of time?
Day of Week 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 637th sisyphus-ppcg 🇦🇺 840 48 2ms 24 Apr 2023 637th Lydxn 🇨🇦 840 48 2ms 2 May 2023 637th MeWhenI 🇻🇦 840 48 2ms 26 May 2023 637th ovs-code 🇩🇪 840 48 3ms 15 Aug 2023 637th retrohun 840 48 2ms 29 Jun 2024 637th DialFrost 🇸🇬 840 48 2ms 22 Dec 2024 637th Salutations45 840 48 2ms 7 Oct 2025 637th edsrzf 🇳🇿 840 48 3ms 5 Jan 2026 649th keelimeguy 🇺🇸 840 78 15ms 16 Nov 2023 649th gallium-gonzollium 840 78 25ms 25 Aug 2024 651st sean-niemann 🇺🇸 840 161 4ms 21 Apr 2025 651st GolfingSuccess 🇬🇷 840 161 4ms 20 Nov 2025 653rd MeWhenI 🇻🇦 839 53 9ms 28 Sep 2024 654th emgordon154 838 135 136ms 29 Dec 2025 655th Yewzir 🇧🇪 837 71 382ms 19 Nov 2023 656th CLOStrophobic 🇮🇹 836 89 8ms 6 May 2025 657th LogicalJoe 836 102 2ms 1 May 2023 658th Shanethegamer 🇺🇸 835 42 76ms 25 Mar 2024 658th MeWhenI 🇻🇦 835 42 75ms 2 Aug 2024 658th JOrE20 835 42 74ms 26 Feb 2026 661st Lydxn 🇨🇦 835 115 12ms 17 Apr 2023 662nd Steffan153 🇫🇮 834 162 4ms 29 Jan 2024 663rd dvargas46 🇺🇸 833 98 103ms 18 Apr 2023 664th 0xjac 🇨🇭 833 128 294ms 11 Jun 2025 665th SirBogman 🇺🇸 832 57 125ms 23 Jan 2024 666th PowershellKnut 🇳🇴 832 81 66ms 7 Jan 2024 667th DialFrost 🇸🇬 832 136 119ms 29 Dec 2025 668th edsrzf 🇳🇿 832 191 32ms 13 Feb 2026 669th jipsong 🇩🇪 831 65 2,635ms 9 Jun 2025 670th Yewzir 🇧🇪 830 70 10ms 14 Dec 2023 670th emgordon154 830 70 11ms 6 Dec 2024 672nd JarrodCope 829 71 381ms 19 Apr 2024 673rd GolfingSuccess 🇬🇷 829 124 440ms 30 Dec 2024 674th Yewzir 🇧🇪 828 116 145ms 30 Apr 2023 675th jipsong 🇩🇪 827 101 3ms 9 Feb 2025 675th snoozingnewt 🇨🇦 827 101 4ms 12 Dec 2025 677th xsot 🇸🇬 824 54 9ms 28 Sep 2024 678th primo-ppcg 🇹🇭 824 206 43ms 26 Apr 2025 678th marshallward 🇺🇸 824 206 41ms 7 May 2025 680th KrausRaus 🇺🇸 823 53 6ms 21 Apr 2023 680th Shanethegamer 🇺🇸 823 53 6ms 2 Jul 2023 680th Kokusui 🇯🇵 823 53 6ms 4 Oct 2024 680th Salutations45 823 53 5ms 21 Nov 2024 684th GrayJoKing 🇦🇺 823 137 17ms 3 May 2023 685th fuzzylojik-golf 🇺🇸 822 105 9ms 14 Oct 2023 685th jkelly467 822 105 10ms 8 Jan 2026 687th MeWhenI 🇻🇦 820 207 40ms 29 Apr 2025 688th AtengChen 819 80 23ms 31 Aug 2024 689th mtirado1 819 102 4ms 17 Apr 2023 689th NickTheEASDude 🇺🇸 819 102 3ms 27 Mar 2024 691st MeWhenI 🇻🇦 819 165 26ms 20 Dec 2023 692nd Steffan153 🇫🇮 819 194 32ms 12 Feb 2026 693rd JayXon 🇺🇸 819 307 1,694ms 22 Apr 2024 694th emgordon154 818 328 1,484ms 6 Nov 2025 695th sisyphus-ppcg 🇦🇺 817 100 8ms 21 Apr 2023 696th Shanethegamer 🇺🇸 816 89 197ms 24 May 2025 696th sean-niemann 🇺🇸 816 89 211ms 25 May 2025 696th MeWhenI 🇻🇦 816 89 177ms 32 hours ago 699th Yewzir 🇧🇪 816 126 443ms 6 May 2024 700th MeWhenI 🇻🇦 816 196 919ms 27 Feb 2026 701st sean-niemann 🇺🇸 816 199 5ms 4 Jul 2025 702nd Ripick 814 73 391ms 11 Jul 2024 703rd KatieLG 🇬🇧 814 106 9ms 24 Apr 2023 704th dokutan 814 151 601ms 7 Nov 2025 705th GrayJoKing 🇦🇺 814 221 19ms 31 Jul 2023 706th KatieLG 🇬🇧 813 75 367ms 7 Jan 2026 707th gnlow 🇰🇷 812 83 53ms 11 Feb 2025 707th LarsFredrikHolstTry 812 83 49ms 28 Oct 2025 709th Bubbler-4 812 85 314ms 17 Apr 2023 710th 2bular 812 95 3ms 3 Aug 2025 711th sisyphus-ppcg 🇦🇺 811 103 4ms 5 Oct 2023 711th dokutan 811 103 4ms 14 Sep 2024 713th edsrzf 🇳🇿 810 159 43ms 1 Sep 2025 714th dokutan 807 90 242ms 29 Jun 2024 715th nwellnhof 🇩🇪 807 119 4ms 28 Apr 2023 716th canissimia 🇦🇶 807 458 45ms 8 Jan 2024 717th snoozingnewt 🇨🇦 806 50 3ms 12 Dec 2025 718th plittlewood 806 73 383ms 16 Apr 2025 719th acotis 806 229 241ms 15 Dec 2025 720th anter69 🇭🇺 805 55 1,384ms 10 Feb 2026 First Prev 641–720 of 1,507 Next Last