The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 5 days. Why not try and solve them ahead of time?
Happy Numbers 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 555th sean-niemann 🇺🇸 899 78 118ms 7 Dec 2025 555th Steffan153 🇫🇮 899 78 113ms 27 days ago 563rd edsrzf 🇳🇿 898 63 137ms 24 Feb 2026 564th GrayJoKing 🇦🇺 897 68 6ms 26 Feb 2026 564th Steffan153 🇫🇮 897 68 6ms 26 Feb 2026 566th thospel 896 42 165ms 25 Jun 2018 566th Lydxn 🇨🇦 896 42 150ms 21 Feb 2023 568th MeWhenI 🇻🇦 896 93 1ms 18 May 2022 569th ETHproductions 🇺🇸 895 67 13ms 14 Apr 2018 570th DaDerpDuck 895 75 1ms 24 Jan 2021 571st DialFrost 🇸🇬 894 68 2,473ms 25 Dec 2024 571st GolfingSuccess 🇬🇷 894 68 4ms 11 Sep 2025 571st albanian-laundromat 894 68 4ms 20 days ago 574th marcin7Cd 894 85 5ms 15 Feb 2021 574th primo-ppcg 🇹🇭 894 85 5ms 1 Mar 2021 574th CLOStrophobic 🇮🇹 894 85 5ms 14 Feb 2025 577th primo-ppcg 🇹🇭 894 91 127ms 14 Jan 2022 578th lifthrasiir 🇰🇷 893 28 3ms 29 Nov 2024 579th Constructor7 893 68 10ms 24 Feb 2018 579th GolfingSuccess 🇬🇷 893 68 9ms 26 Mar 2018 579th kmaork 🇮🇱 893 68 9ms 18 Apr 2018 579th edre 893 68 9ms 30 Apr 2018 579th j55d 893 68 9ms 19 Sep 2018 579th daedals 893 68 9ms 16 Apr 2019 579th villfa 893 68 9ms 20 May 2019 579th TFeld00 🇩🇰 893 68 9ms 31 May 2019 579th marcin7Cd 893 68 10ms 27 Aug 2019 579th xorraxrax 893 68 9ms 19 Oct 2019 579th jiaminglimjm 🇲🇾 893 68 9ms 12 Dec 2019 579th SirBogman 🇺🇸 893 68 10ms 4 Jan 2020 579th thisishowmymindworks 🇳🇴 893 68 9ms 22 Jul 2020 579th ToriTheChicken 893 68 9ms 23 Jul 2020 579th ydevor 🇮🇱 893 68 10ms 26 Nov 2020 579th anter69 🇭🇺 893 68 10ms 14 Jan 2021 579th HETHAT 🇩🇿 893 68 10ms 31 Jan 2021 579th vezzick 893 68 9ms 7 Mar 2021 579th Indivicivet 893 68 9ms 26 Mar 2021 579th emplv 🇱🇻 893 68 9ms 31 Aug 2021 579th MichaelMBradley 🇨🇦 893 68 10ms 11 Jun 2022 579th janbehrens 🇩🇪 893 68 10ms 4 Jul 2022 579th betaveros 893 68 9ms 9 Aug 2022 579th 5quiwyrm 893 68 10ms 20 Aug 2022 579th PowerR0 893 68 9ms 25 Aug 2022 579th ItsMeNoobieboy 893 68 9ms 21 Dec 2022 579th scpchicken 🇵🇼 893 68 9ms 28 Jan 2023 579th CheeseCake628 🇳🇴 893 68 16ms 16 Feb 2023 579th Just4FunCoder 893 68 10ms 22 Mar 2023 579th fourth-bit 893 68 9ms 11 Jul 2023 579th RYNO8 893 68 9ms 22 Aug 2023 579th Yewzir 🇧🇪 893 68 9ms 6 Oct 2023 579th keelimeguy 🇺🇸 893 68 17ms 19 Oct 2023 579th 1231234md5 🇨🇳 893 68 10ms 13 Dec 2023 579th stackofbears 893 68 9ms 27 Dec 2023 579th CutSandstone 893 68 10ms 5 Jul 2024 579th Bulmenisaurus 893 68 9ms 17 Jul 2024 579th codingisgreatbutiamnot 893 68 16ms 12 Aug 2024 579th Troon 893 68 10ms 11 Feb 2025 579th plcc0 893 68 11ms 20 Feb 2025 579th albanian-laundromat 893 68 9ms 30 Jun 2025 579th SanderRuud 893 68 9ms 13 Jul 2025 579th qpwoeirut 893 68 10ms 1 Oct 2025 579th countlpaul-dotcom 893 68 9ms 19 Oct 2025 579th SectorCorruptor 893 68 10ms 8 Feb 2026 624th edsrzf 🇳🇿 893 90 39ms 21 Dec 2025 625th MeWhenI 🇻🇦 893 92 24ms 13 Jul 2021 626th pardouin 🇫🇷 893 114 284ms 24 Aug 2024 626th DialFrost 🇸🇬 893 114 281ms 26 Dec 2024 626th snoozingnewt 🇨🇦 893 114 281ms 29 Nov 2025 629th stackofbears 892 33 34ms 14 Mar 2025 630th GrayJoKing 🇦🇺 892 72 36ms 14 Jun 2022 630th primo-ppcg 🇹🇭 892 72 36ms 21 Jun 2022 630th 386asm 🇺🇸 892 72 37ms 4 May 2023 633rd prplz 🇦🇺 892 80 1ms 20 Oct 2020 633rd primo-ppcg 🇹🇭 892 80 1ms 21 Oct 2020 633rd emgordon154 892 80 1ms 22 Dec 2021 633rd GrayJoKing 🇦🇺 892 80 1ms 13 Mar 2022 633rd jared-hughes 892 80 1ms 30 Mar 2022 633rd janbehrens 🇩🇪 892 80 2ms 26 Nov 2023 633rd Herbert00709 🇵🇱 892 80 2ms 8 Jun 2024 633rd roupiq 🇵🇱 892 80 1ms 9 Jun 2024 First Prev 561–640 of 3,218 Next Last
