The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 44 hours. Why not try and solve them ahead of time?
Farey Sequence 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 snoozingnewt 🇨🇦 569 150 436ms 15 Oct 2025 802nd msbranicky 568 94 436ms 17 Jan 2024 803rd msbranicky 568 128 2,496ms 9 Jan 2025 804th dokutan 568 129 438ms 26 Oct 2024 804th snoozingnewt 🇨🇦 568 129 381ms 15 Oct 2025 806th Ripick 566 99 12ms 1 Dec 2023 806th hellwue 566 99 11ms 22 Feb 2024 808th madeforlosers 563 112 41ms 8 Dec 2023 809th Natanaelel 🇸🇪 562 133 19ms 29 Dec 2023 810th AstroOrbis 561 100 11ms 22 Feb 2026 811th snoozingnewt 🇨🇦 561 170 25ms 15 Oct 2025 812th snoozingnewt 🇨🇦 560 130 119ms 15 Oct 2025 813th Chinay-Domitrix 🇺🇸 559 130 2,621ms 4 Nov 2025 813th dokutan 559 130 8ms 25 Feb 2026 815th jerrandolph 558 173 286ms 22 Dec 2023 816th 051 🇸🇬 555 101 11ms 24 Dec 2023 817th Protothor 555 104 11ms 27 Feb 2026 818th mrmena 🇦🇺 553 114 43ms 11 May 2024 819th kkoenig 552 117 2ms 22 Dec 2023 819th tsschepens 552 117 2ms 26 Feb 2026 821st JRaspass 🇬🇧 551 73 128ms 4 Jan 2024 822nd dokutan 551 132 2,677ms 26 Oct 2024 823rd msbranicky 551 155 1,449ms 2 Jan 2024 824th WillConker 550 102 28ms 10 Mar 2024 825th msbranicky 549 112 86ms 8 Jan 2024 826th MeWhenI 🇻🇦 548 115 68ms 1 Dec 2023 827th Yewzir 🇧🇪 547 139 124ms 5 Feb 2024 828th snoozingnewt 🇨🇦 546 156 3ms 15 Oct 2025 829th MWI-polygolf 545 137 4ms 7 Dec 2023 830th Apataras 545 139 424ms 3 Jul 2025 831st markusgraube 544 103 11ms 22 Jun 2024 832nd HumanoidCPU 543 119 2ms 5 Mar 2024 833rd dokutan 542 77 41ms 29 Oct 2024 834th KadinSchultz 539 104 10ms 4 Dec 2023 834th cros107 🇦🇺 539 104 11ms 26 Dec 2023 834th JunkIce 539 104 12ms 24 Nov 2024 837th janbehrens 🇩🇪 538 120 2ms 22 Dec 2023 838th CatsAreFluffy 537 159 73ms 31 Jan 2024 839th msbranicky 536 117 124ms 2 Jan 2024 840th msbranicky 536 151 148ms 2 Jan 2024 841st blaztoma 🇱🇹 535 78 40ms 4 Nov 2025 842nd tomh1012 535 108 11ms 2 days ago 843rd madex 🇩🇪 534 105 12ms 21 May 2024 844th MeWhenI 🇻🇦 532 84 3ms 1 Dec 2023 845th janbehrens 🇩🇪 531 138 414ms 17 Apr 2025 846th Yewzir 🇧🇪 529 150 3ms 29 Mar 2024 847th HumanoidCPU 529 153 104ms 16 Nov 2025 848th YAJUE114514 527 138 146ms 23 Jul 2025 849th anarconic 526 125 2ms 11 Dec 2023 850th Yewzir 🇧🇪 525 117 89ms 5 Feb 2024 851st CarsonChr 🇺🇸 524 145 124ms 24 Dec 2023 852nd msbranicky 522 152 3ms 2 Jan 2024 853rd snoozingnewt 🇨🇦 521 121 1,347ms 15 Oct 2025 854th steffan-polygolf 521 133 12ms 29 Feb 2024 855th neihousaigaai 519 108 11ms 11 Feb 2024 856th dokutan 519 121 120ms 29 Oct 2024 857th JDiLenarda 🇫🇷 517 122 1,277ms 13 Sep 2024 858th snoozingnewt 🇨🇦 517 125 2ms 15 Oct 2025 859th weliveinhell 🇭🇹 517 147 131ms 2 Dec 2023 860th Bodo171 514 109 11ms 1 Jul 2024 860th trist224 🇫🇷 514 109 11ms 3 Aug 2025 862nd janAkali 🇷🇺 514 122 1,898ms 10 days ago 863rd JunkIce 513 104 373ms 3 Dec 2024 864th Kokusui 🇯🇵 513 108 5ms 26 Jul 2024 865th rollershutter 510 110 13ms 20 Dec 2023 865th fourth-bit 510 110 23ms 1 Jul 2024 865th jipsong 🇩🇪 510 110 21ms 5 Jul 2025 868th msbranicky 510 149 115ms 1 Jan 2024 869th snoozingnewt 🇨🇦 509 136 9ms 15 Oct 2025 870th dokutan 509 156 3ms 26 Oct 2024 871st snoozingnewt 🇨🇦 508 143 2,552ms 15 Oct 2025 872nd msbranicky 507 116 163ms 1 Jan 2024 873rd typeswitch-dev 🇵🇹 507 151 5ms 25 Jun 2024 874th alphafalfa 506 107 2ms 26 Aug 2024 875th dokutan 505 100 7ms 28 Oct 2024 876th minhtrancccp 505 111 11ms 1 Dec 2023 876th croc54 505 111 21ms 30 Dec 2024 876th Mikey-Beep 🇬🇧 505 111 21ms 24 Jul 2025 876th CommandLeo 🇮🇹 505 111 21ms 1 Nov 2025 880th MeWhenI 🇻🇦 505 132 95ms 1 Dec 2023 First Prev 801–880 of 1,536 Next Last