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 372nd zach333 921 46 10ms 20 Jul 2024 372nd zacjl 921 46 18ms 20 Sep 2024 372nd FlyingPenguin223 921 46 10ms 17 Dec 2024 372nd Mukundan314 921 46 16ms 25 Apr 2025 372nd fuzzylojik-golf 🇺🇸 921 46 16ms 28 Jun 2025 372nd CaedenHarper 🇨🇦 921 46 9ms 24 Jul 2025 372nd qpwoeirut 921 46 10ms 24 Aug 2025 372nd Babafaba 921 46 16ms 13 Oct 2025 372nd 09cf 921 46 16ms 25 Nov 2025 372nd edsrzf 🇳🇿 921 46 16ms 14 Dec 2025 372nd blaztoma 🇱🇹 921 46 16ms 16 Jan 2026 412th xsot 🇸🇬 921 48 5ms 13 Apr 2024 412th sean-niemann 🇺🇸 921 48 4ms 16 Jul 2024 414th Lydxn 🇨🇦 920 68 453ms 27 Feb 2022 414th sean-niemann 🇺🇸 920 68 434ms 28 Feb 2022 414th JayXon 🇺🇸 920 68 437ms 28 Feb 2022 414th GrayJoKing 🇦🇺 920 68 458ms 28 Feb 2022 414th MeWhenI 🇻🇦 920 68 438ms 10 Oct 2022 414th ovs-code 🇩🇪 920 68 439ms 31 Dec 2022 414th Steffan153 🇫🇮 920 68 435ms 1 Jan 2023 414th DialFrost 🇸🇬 920 68 433ms 8 Nov 2023 414th dokutan 920 68 444ms 27 Sep 2025 414th fuzzylojik-golf 🇺🇸 920 68 428ms 51 mins ago 424th primo-ppcg 🇹🇭 919 45 1ms 7 Nov 2022 424th xsot 🇸🇬 919 45 3ms 18 Mar 2024 426th btnlq 918 35 3ms 17 Aug 2024 426th ovs-code 🇩🇪 918 35 3ms 20 Aug 2024 428th nwellnhof 🇩🇪 918 57 1ms 11 Feb 2020 428th primo-ppcg 🇹🇭 918 57 1ms 22 Aug 2020 428th Irratix 🇳🇱 918 57 1ms 13 Jun 2022 428th madex 🇩🇪 918 57 2ms 12 Nov 2022 428th inventshah 918 57 2ms 26 Jan 2023 428th xsot 🇸🇬 918 57 2ms 16 Apr 2023 428th JohandeRuiter 🇳🇱 918 57 2ms 25 Oct 2023 428th dokutan 918 57 2ms 25 Sep 2024 428th FlyingPenguin223 918 57 1ms 10 Feb 2025 428th kdx2a 918 57 1ms 11 Feb 2025 428th Mukundan314 918 57 2ms 26 Apr 2025 428th fuzzylojik-golf 🇺🇸 918 57 1ms 28 Jun 2025 428th Yax42 🇫🇷 918 57 2ms 15 Oct 2025 428th 09cf 918 57 2ms 25 Nov 2025 442nd janlelis 917 35 37ms 7 Feb 2021 442nd Steffan153 🇫🇮 917 35 36ms 4 days ago 444th GrayJoKing 🇦🇺 917 44 5ms 31 Jan 2025 445th Attero 🇸🇪 917 46 1ms 9 May 2020 445th Waffle3z 917 46 1ms 11 Jul 2021 445th GrayJoKing 🇦🇺 917 46 2ms 9 Feb 2022 445th jared-hughes 917 46 1ms 10 Mar 2022 445th MeWhenI 🇻🇦 917 46 1ms 31 Dec 2022 445th b10011 🇫🇮 917 46 2ms 5 Jan 2023 445th sean-niemann 🇺🇸 917 46 1ms 12 Jan 2023 445th DialFrost 🇸🇬 917 46 2ms 8 Nov 2023 445th dokutan 917 46 1ms 25 Sep 2024 445th FlyingPenguin223 917 46 1ms 17 Dec 2024 445th edsrzf 🇳🇿 917 46 2ms 14 Dec 2025 445th fuzzylojik-golf 🇺🇸 917 46 2ms 6 mins ago 457th olivermrose 🇺🇸 917 51 118ms 23 Aug 2021 458th lynn 917 60 25ms 11 Jul 2023 458th Lydxn 🇨🇦 917 60 25ms 11 Jul 2023 458th Steffan153 🇫🇮 917 60 27ms 4 days ago 461st primo-ppcg 🇹🇭 916 45 146ms 6 Sep 2023 461st Steffan153 🇫🇮 916 45 134ms 4 days ago 463rd Lydxn 🇨🇦 915 41 1ms 8 Oct 2023 463rd MeWhenI 🇻🇦 915 41 1ms 18 Aug 2024 465th DialFrost 🇸🇬 914 28 324ms 14 Dec 2025 466th GrayJoKing 🇦🇺 914 53 129ms 18 Oct 2022 467th Lydxn 🇨🇦 914 55 4ms 16 Jul 2023 468th voytxt 🇨🇿 913 42 150ms 3 Aug 2024 468th pardouin 🇫🇷 913 42 136ms 5 Aug 2024 470th somebody1234 912 43 10ms 7 Dec 2018 470th dymowski 912 43 9ms 7 Jul 2019 470th KrausRaus 🇺🇸 912 43 9ms 22 Aug 2019 470th handisb 912 43 11ms 31 Aug 2019 470th dorinoltean 912 43 9ms 2 Oct 2019 470th oitio 912 43 10ms 12 Feb 2020 470th shuding 912 43 8ms 27 Apr 2020 470th taklam 912 43 10ms 20 May 2020 470th raphaelimahorn 912 43 10ms 4 Sep 2020 470th revlayle 🇺🇸 912 43 10ms 14 Sep 2020 470th PatrickStephansen 🇿🇦 912 43 10ms 15 Oct 2020 First Prev 401–480 of 4,855 Next Last