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 bytes. 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 Bytes Time Submitted 635th Waffle3z 902 47 16ms 14 Jul 2021 635th janbehrens 🇩🇪 902 47 16ms 21 Oct 2021 635th annaproxy 902 47 16ms 13 Dec 2021 635th pxeger 🇬🇧 902 47 15ms 16 Feb 2022 635th sisyphus-ppcg 🇦🇺 902 47 17ms 19 Feb 2022 635th shellbertt 🇨🇦 902 47 15ms 2 May 2022 635th mrnomm 902 47 16ms 24 Aug 2022 635th jumelet 🇳🇱 902 47 16ms 23 Dec 2022 635th thatbirdguythatuknownot 902 47 20ms 3 Jan 2023 635th MichalMarsalek 🇨🇿 902 47 10ms 23 Feb 2023 635th AlexanderFair 902 47 17ms 15 Jun 2023 635th inventshah 902 47 21ms 18 Jul 2023 635th ListeriaM 902 47 19ms 24 Aug 2023 635th bizy-coder 902 47 18ms 2 Feb 2024 635th BREMAUCY 🇫🇷 902 47 21ms 25 Mar 2024 635th Bulmenisaurus 902 47 19ms 4 Aug 2024 635th voytxt 🇨🇿 902 47 16ms 20 Sep 2024 635th dokutan 902 47 10ms 25 Sep 2024 635th lifthrasiir 🇰🇷 902 47 17ms 20 Nov 2024 635th plcc0 902 47 10ms 6 Mar 2025 635th jipsong 🇩🇪 902 47 10ms 1 Apr 2025 635th KasperKivimaeki 🇫🇮 902 47 15ms 14 May 2025 635th keelimeguy 🇺🇸 902 47 20ms 16 May 2025 635th Flekay 🇩🇪 902 47 16ms 9 Aug 2025 635th janlelis 902 47 16ms 14 Aug 2025 635th snoozingnewt 🇨🇦 902 47 16ms 26 Sep 2025 635th Emutis 🇱🇹 902 47 19ms 25 Oct 2025 635th CommandLeo 🇮🇹 902 47 17ms 30 Nov 2025 635th Lv0Sys 🇵🇱 902 47 16ms 2 Dec 2025 670th neel11235813 902 51 1,349ms 4 Jan 2023 670th MeWhenI 🇻🇦 902 51 1,349ms 8 Jun 2023 670th dokutan 902 51 1,286ms 14 Oct 2024 670th DialFrost 🇸🇬 902 51 1,281ms 9 Mar 2025 670th sean-niemann 🇺🇸 902 51 1,333ms 18 Apr 2025 670th fuzzylojik-golf 🇺🇸 902 51 1,359ms 2 Sep 2025 676th sean-niemann 🇺🇸 901 38 79ms 14 Sep 2023 676th blaztoma 🇱🇹 901 38 75ms 2 Nov 2025 678th retrohun 901 46 1ms 16 Jun 2024 679th arjanadriaanse 🇳🇱 901 52 121ms 1 Jan 2022 680th Shanethegamer 🇺🇸 901 79 59ms 12 Jan 2022 680th Yewzir 🇧🇪 901 79 57ms 9 Dec 2023 680th oceko 901 79 58ms 19 Feb 2024 680th CaedenHarper 🇨🇦 901 79 62ms 1 Feb 2025 680th yanjs 901 79 480ms 10 Jul 2025 680th AutumnWind75 901 79 446ms 10 Dec 2025 680th bac0id 901 79 110ms 27 Jan 2026 687th MeWhenI 🇻🇦 899 54 111ms 15 Oct 2022 687th Yax42 🇫🇷 899 54 104ms 5 Oct 2025 689th AlephSquirrel 899 60 5ms 13 Mar 2023 689th Lydxn 🇨🇦 899 60 15ms 31 Jan 2025 689th edsrzf 🇳🇿 899 60 14ms 14 Dec 2025 692nd billings7 🇬🇧 898 63 367ms 21 Nov 2021 692nd ChristophHornung 898 63 374ms 21 Nov 2021 692nd KatieLG 🇬🇧 898 63 365ms 17 Oct 2022 695th DialFrost 🇸🇬 896 36 3ms 11 Aug 2024 695th MeWhenI 🇻🇦 896 36 3ms 12 Aug 2024 695th sean-niemann 🇺🇸 896 36 3ms 13 Aug 2024 695th GrayJoKing 🇦🇺 896 36 3ms 26 Aug 2024 695th lynn 896 36 3ms 21 Dec 2024 700th nwellnhof 🇩🇪 896 89 295ms 3 Sep 2020 700th MeWhenI 🇻🇦 896 89 273ms 10 Oct 2022 700th DialFrost 🇸🇬 896 89 285ms 8 Nov 2023 700th ovs-code 🇩🇪 896 89 6ms 8 Jul 2024 700th dokutan 896 89 285ms 25 Sep 2024 700th fuzzylojik-golf 🇺🇸 896 89 272ms 15 Jul 2025 700th KasperKivimaeki 🇫🇮 896 89 273ms 29 Sep 2025 700th edsrzf 🇳🇿 896 89 285ms 21 Dec 2025 708th Yewzir 🇧🇪 895 70 443ms 17 Nov 2023 709th canissimia 🇦🇶 895 83 6ms 1 Aug 2023 710th MeWhenI 🇻🇦 894 45 139ms 3 Aug 2024 710th dokutan 894 45 135ms 25 Sep 2024 712th clockworknazo 894 54 3ms 23 Oct 2022 713th Shanethegamer 🇺🇸 894 64 107ms 15 Apr 2025 713th snoozingnewt 🇨🇦 894 64 110ms 1 Dec 2025 713th emgordon154 894 64 108ms 1 Dec 2025 713th DialFrost 🇸🇬 894 64 114ms 3 Dec 2025 713th sean-niemann 🇺🇸 894 64 100ms 4 Jan 2026 713th Steffan153 🇫🇮 894 64 112ms 27 Feb 2026 719th primo-ppcg 🇹🇭 893 36 33ms 8 Dec 2018 719th nwellnhof 🇩🇪 893 36 37ms 28 Apr 2020 First Prev 641–720 of 4,877 Next Last