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?
Leap Years 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 469th toubsen 🇩🇪 912 43 10ms 8 Jan 2021 469th omurakazuaki 🇯🇵 912 43 13ms 19 Feb 2021 469th lukasmoellerch 912 43 11ms 15 Mar 2021 469th MossGrass 🇺🇸 912 43 10ms 21 May 2021 469th wansacis 🇩🇪 912 43 11ms 28 Jul 2021 469th lynn 912 43 10ms 10 Sep 2021 469th alasdair-greenland 912 43 9ms 11 Nov 2021 469th emgordon154 912 43 10ms 23 Nov 2021 469th solmyr2000 912 43 10ms 8 Jun 2022 469th AlephSquirrel 912 43 9ms 18 Jul 2022 469th FlorianCassayre 🇫🇷 912 43 10ms 27 Sep 2022 469th BloodStormKnight 912 43 9ms 13 Oct 2022 469th LukeBridges 🇬🇧 912 43 10ms 17 Oct 2022 469th astonm 912 43 10ms 17 Oct 2022 469th Maznek 912 43 10ms 6 Jun 2023 469th jbt 912 43 9ms 26 Dec 2023 469th wlaud9 912 43 10ms 8 Feb 2024 469th weliveinhell 🇭🇹 912 43 9ms 23 Jul 2024 469th acollett89 912 43 9ms 12 Jun 2025 500th m-tkach 🇺🇦 911 78 56ms 24 Oct 2022 500th NDR0216 🇹🇼 911 78 62ms 9 May 2024 500th yeminghan2021 911 78 65ms 2 Feb 2025 500th qwertyuiop3 🇷🇺 911 78 59ms 2 Jun 2025 500th emgordon154 911 78 60ms 7 Feb 2026 505th DialFrost 🇸🇬 910 45 2,577ms 23 Oct 2024 505th dokutan 910 45 2,405ms 23 Oct 2024 505th sean-niemann 🇺🇸 910 45 2,527ms 23 Oct 2024 505th MeWhenI 🇻🇦 910 45 2,644ms 24 Oct 2024 505th pardouin 🇫🇷 910 45 2,392ms 24 Oct 2024 505th Chinay-Domitrix 🇺🇸 910 45 2,510ms 25 Feb 2026 511th UnderKoen 🇳🇱 910 72 2ms 16 Jun 2025 512th lynn 909 22 38ms 26 Jul 2022 512th SirBogman 🇺🇸 909 22 36ms 18 Sep 2022 512th pardouin 🇫🇷 909 22 39ms 24 Oct 2024 512th saito-ta 🇯🇵 909 22 41ms 28 Aug 2025 512th fuzzylojik-golf 🇺🇸 909 22 42ms 4 mins ago 517th retrohun 909 31 4ms 30 Apr 2019 517th scpchicken 🇵🇼 909 31 3ms 18 Jun 2023 517th fuzzylojik-golf 🇺🇸 909 31 3ms 22 May 2025 520th antimon2 🇯🇵 908 36 379ms 25 Jan 2021 521st Steffan153 🇫🇮 908 53 4ms 18 Feb 2023 521st xsot 🇸🇬 908 53 4ms 11 Feb 2024 521st sean-niemann 🇺🇸 908 53 4ms 25 Mar 2025 524th Bubbler-4 907 24 2ms 10 Jan 2022 524th GrayJoKing 🇦🇺 907 24 2ms 2 Feb 2022 524th lynn 907 24 2ms 27 May 2022 524th bstrat 907 24 2ms 9 Oct 2024 528th sean-niemann 🇺🇸 907 54 7ms 23 Jun 2025 529th janbehrens 🇩🇪 907 69 449ms 24 Mar 2022 529th voytxt 🇨🇿 907 69 440ms 7 Apr 2022 529th Yewzir 🇧🇪 907 69 443ms 17 Nov 2023 532nd xsot 🇸🇬 906 40 722ms 22 Feb 2026 533rd MeWhenI 🇻🇦 906 45 1,033ms 12 Oct 2022 533rd sean-niemann 🇺🇸 906 45 87ms 6 May 2024 535th primo-ppcg 🇹🇭 906 51 4ms 20 May 2023 536th sisyphus-ppcg 🇦🇺 905 34 1,255ms 26 Mar 2021 536th dokutan 905 34 1,299ms 25 Sep 2024 538th sean-niemann 🇺🇸 905 41 433ms 17 Jan 2024 538th DialFrost 🇸🇬 905 41 426ms 17 Jan 2024 538th GrayJoKing 🇦🇺 905 41 430ms 18 Jan 2024 538th b-illy 🇬🇧 905 41 417ms 7 Sep 2024 542nd masterada 905 85 296ms 26 Mar 2021 542nd stefangimmillaro 905 85 283ms 4 Aug 2023 542nd Steffan153 🇫🇮 905 85 278ms 3 Aug 2024 545th lynn 904 28 33ms 12 Apr 2021 545th HPWiz 🇳🇿 904 28 34ms 17 Apr 2021 545th ovs-code 🇩🇪 904 28 32ms 6 Feb 2024 548th canissimia 🇦🇶 904 179 1ms 11 Sep 2021 549th MeWhenI 🇻🇦 903 28 2ms 25 Mar 2025 550th emplv 🇱🇻 902 49 5ms 15 Apr 2021 550th janbehrens 🇩🇪 902 49 4ms 22 May 2021 550th rucin93 🇵🇱 902 49 4ms 3 Dec 2021 550th GrayJoKing 🇦🇺 902 49 4ms 9 Feb 2022 550th voytxt 🇨🇿 902 49 5ms 16 May 2022 550th MeWhenI 🇻🇦 902 49 4ms 28 May 2023 550th stefangimmillaro 902 49 4ms 22 Aug 2023 550th Argeento 🇵🇱 902 49 4ms 25 Aug 2023 550th DialFrost 🇸🇬 902 49 5ms 8 Nov 2023 550th Shanethegamer 🇺🇸 902 49 5ms 9 Jan 2024 560th Attero 🇸🇪 902 58 1ms 12 Mar 2020 First Prev 481–560 of 4,851 Next Last