The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 37 hours. Why not try and solve them ahead of time?
Leyland 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 638th lemogne 737 82 10ms 10 Aug 2021 638th j-Ewan 737 82 14ms 11 Mar 2022 638th TheoKeller1 737 82 17ms 6 Jun 2023 638th Andriamanitra 🇫🇮 737 82 11ms 26 Jul 2023 638th dirckvdende 737 82 9ms 21 Jul 2025 638th FoxInTheClouds 737 82 10ms 13 Feb 2026 647th Shanethegamer 🇺🇸 737 158 30ms 20 Sep 2023 648th cywong-amino 🇭🇰 736 91 10ms 30 Jul 2020 648th Shanethegamer 🇺🇸 736 91 9ms 10 Mar 2022 648th dmrichwa 🇺🇸 736 91 13ms 4 Oct 2022 651st MeWhenI 🇻🇦 736 105 12ms 9 May 2024 652nd Herbert00709 🇵🇱 736 169 66ms 4 days ago 653rd Irratix 🇳🇱 734 93 118ms 1 Nov 2021 654th GrayJoKing 🇦🇺 734 150 4ms 19 Nov 2025 655th GrayJoKing 🇦🇺 733 133 465ms 6 Jun 2022 656th MeWhenI 🇻🇦 732 77 248ms 29 Jan 2023 657th olivermrose 🇺🇸 731 58 42ms 3 Oct 2021 657th stefangimmillaro 731 58 37ms 27 Oct 2021 657th SirBogman 🇺🇸 731 58 37ms 8 Jun 2022 657th sisyphus-ppcg 🇦🇺 731 58 40ms 11 Jul 2022 657th tatzyr 🇯🇵 731 58 41ms 24 Nov 2024 657th KatieLG 🇬🇧 731 58 35ms 2 Oct 2025 663rd snoozingnewt 🇨🇦 731 77 5ms 13 Oct 2025 664th KrausRaus 🇺🇸 731 96 11ms 21 Dec 2021 665th annaproxy 731 155 404ms 1 Apr 2022 665th snoozingnewt 🇨🇦 731 155 416ms 13 Oct 2025 667th Andriamanitra 🇫🇮 728 59 471ms 26 Jul 2023 668th bstrautin 728 83 10ms 27 Jul 2020 668th neihousaigaai 728 83 10ms 8 May 2021 668th commandz0 🇺🇸 728 83 14ms 5 Sep 2022 668th glesnick 728 83 10ms 12 Oct 2022 668th AbhilashaTandon 728 83 9ms 23 Nov 2022 668th badboj40 728 83 10ms 27 Dec 2022 668th Just4FunCoder 728 83 17ms 22 Mar 2023 668th cingulataluke 728 83 13ms 28 Aug 2023 668th levavft 728 83 14ms 26 Oct 2023 668th Anonymousellama21 728 83 9ms 9 Aug 2024 668th Andre3582 728 83 10ms 10 Oct 2025 679th KrausRaus 🇺🇸 728 92 11ms 12 Nov 2020 679th SadiinsoSnowfall 🇫🇷 728 92 15ms 19 Feb 2024 681st roupiq 🇵🇱 728 171 2,798ms 4 days ago 682nd NewDefectus 🇮🇱 726 129 144ms 18 Feb 2021 683rd jared-hughes 725 104 14ms 27 Nov 2021 684th inventshah 725 110 2ms 12 Sep 2022 685th emgordon154 724 85 1,220ms 11 Jan 2026 686th perlebach 🇨🇿 724 143 2,673ms 10 Jun 2025 687th Aurel300 🇨🇭 724 165 220ms 20 Jun 2024 688th gjoacorp 🇬🇧 723 172 2,989ms 4 Aug 2025 689th tomh1012 721 157 466ms 5 Sep 2025 690th Alessandro-Balconi 🇮🇹 720 79 90ms 15 Jul 2023 691st Jacob385 720 80 4,372ms 9 Apr 2024 691st commandz0 🇺🇸 720 80 423ms 1 Sep 2025 693rd Indivicivet 720 84 19ms 17 Oct 2021 693rd Nigel-C 720 84 11ms 30 May 2022 693rd OhmNomNom 720 84 11ms 14 Oct 2022 693rd betaveros 720 84 11ms 31 Dec 2022 693rd Lv0Sys 🇵🇱 720 84 10ms 3 Dec 2025 693rd Googolplexo 🇷🇺 720 84 15ms 4 days ago 699th BBoehm 🇩🇪 720 93 10ms 18 Feb 2021 699th helbling 🇨🇭 720 93 11ms 29 May 2024 701st hiddicop 🇸🇪 719 59 36ms 29 Jan 2021 701st Shanethegamer 🇺🇸 719 59 37ms 16 Feb 2023 701st BREMAUCY 🇫🇷 719 59 36ms 21 May 2023 701st Natanaelel 🇸🇪 719 59 37ms 15 Jan 2024 701st snoozingnewt 🇨🇦 719 59 38ms 2 Oct 2025 701st denkyuu1 719 59 36ms 15 Feb 2026 707th albanian-laundromat 719 137 112ms 7 Nov 2025 708th KatieLG 🇬🇧 718 135 2ms 24 Sep 2021 708th emgordon154 718 135 2ms 21 Jun 2024 710th Shanethegamer 🇺🇸 717 158 424ms 9 Apr 2025 711th primo-ppcg 🇹🇭 716 171 427ms 29 Aug 2020 712th okaponta 715 167 243ms 11 Jan 2024 713th TaserTheFox 🇺🇸 714 79 283ms 1 Jun 2023 714th DialFrost 🇸🇬 714 85 9ms 7 Nov 2025 715th janbehrens 🇩🇪 712 85 12ms 29 Oct 2021 716th neihousaigaai 712 94 10ms 18 Apr 2021 716th junkondo-jp 712 94 11ms 8 Jun 2024 716th Yax42 🇫🇷 712 94 12ms 5 Sep 2025 719th ertz1ertz 712 159 393ms 14 Aug 2024 720th HumanEquivalentUnit 711 38 32ms 12 Oct 2020 First Prev 641–720 of 1,899 Next Last