The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 9 hours. 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 880th madex 🇩🇪 839 59 474ms 14 days ago 882nd snoozingnewt 🇨🇦 839 80 1ms 29 Nov 2025 883rd MeWhenI 🇻🇦 839 92 458ms 10 Oct 2022 884th Yewzir 🇧🇪 838 79 2ms 22 Dec 2023 884th albanian-laundromat 838 79 2ms 24 Jun 2025 886th edsrzf 🇳🇿 838 97 126ms 4 Mar 2025 887th SirFireball3521 836 45 171ms 22 Mar 2023 888th GrayJoKing 🇦🇺 836 80 100ms 15 Jul 2023 889th snoozingnewt 🇨🇦 835 84 3ms 9 Dec 2025 890th Shanethegamer 🇺🇸 833 30 3ms 13 Jan 2022 891st PatrickStephansen 🇿🇦 833 72 11ms 3 Nov 2020 891st KatieLG 🇬🇧 833 72 10ms 16 Apr 2021 891st neihousaigaai 833 72 9ms 18 Apr 2021 891st two-bad 🇬🇧 833 72 11ms 25 Feb 2024 895th mogron 832 73 10ms 13 Dec 2019 895th FlorianCassayre 🇫🇷 832 73 9ms 30 Oct 2022 895th StefanHabel 🇨🇦 832 73 9ms 11 Dec 2022 895th duckyluuk 🇳🇱 832 73 4ms 16 Dec 2024 895th DrakeSeteraO 832 73 10ms 25 Oct 2025 900th acacopardo 831 76 15ms 14 Nov 2017 900th MeWhenI 🇻🇦 831 76 14ms 15 Sep 2021 900th DaCuteRaccoon 831 76 14ms 30 Nov 2022 903rd marshallward 🇺🇸 831 81 39ms 2 Sep 2022 904th primo-ppcg 🇹🇭 830 67 143ms 25 Dec 2020 904th lynn 830 67 139ms 18 May 2021 904th Yewzir 🇧🇪 830 67 146ms 17 Sep 2023 904th sean-niemann 🇺🇸 830 67 143ms 8 Oct 2024 908th djeedjay 🇳🇱 830 86 1ms 26 Oct 2020 908th Yewzir 🇧🇪 830 86 1ms 22 Dec 2023 910th fuzzylojik-golf 🇺🇸 830 93 458ms 30 Aug 2025 911th kgodara 830 98 128ms 11 Mar 2023 912th GrayJoKing 🇦🇺 829 53 18ms 10 Apr 2021 912th scpchicken 🇵🇼 829 53 34ms 23 May 2021 912th kurkale6ka 829 53 19ms 16 Jun 2021 912th sean-niemann 🇺🇸 829 53 34ms 7 Sep 2021 912th MeWhenI 🇻🇦 829 53 40ms 15 Sep 2021 912th DaCuteRaccoon 829 53 32ms 30 Nov 2022 912th Steffan153 🇫🇮 829 53 32ms 28 Jan 2023 912th DialFrost 🇸🇬 829 53 33ms 28 Jan 2023 912th snoozingnewt 🇨🇦 829 53 33ms 1 Sep 2024 912th LostSyntax21 🇬🇧 829 53 32ms 8 Jan 2025 912th fuzzylojik-golf 🇺🇸 829 53 19ms 15 Sep 2025 923rd jared-hughes 829 82 116ms 11 Sep 2023 924th edsrzf 🇳🇿 829 108 3ms 15 days ago 925th anter69 🇭🇺 828 57 34ms 3 Aug 2021 925th annaproxy 828 57 34ms 27 Aug 2022 925th BREMAUCY 🇫🇷 828 57 34ms 26 Mar 2024 925th dokutan 828 57 33ms 18 days ago 929th inventshah 827 80 2ms 9 Sep 2022 930th Shanethegamer 🇺🇸 826 64 3ms 25 Apr 2023 931st m-tkach 🇺🇦 825 64 381ms 30 Jan 2024 932nd GolfingSuccess 🇬🇷 825 74 7ms 24 Feb 2026 933rd ovs-code 🇩🇪 824 153 1,750ms 14 Sep 2025 933rd primo-ppcg 🇹🇭 824 153 1,708ms 15 Sep 2025 933rd emgordon154 824 153 1,662ms 16 Sep 2025 933rd Yewzir 🇧🇪 824 153 1,881ms 14 Nov 2025 937th didion0 🇺🇸 822 73 12ms 22 Apr 2021 937th itsh01 822 73 12ms 16 Aug 2021 937th c0d3-4-F00d 🇩🇪 822 73 9ms 5 Jan 2022 937th DaCuteRaccoon 822 73 9ms 30 Nov 2022 937th janbehrens 🇩🇪 822 73 10ms 17 Jun 2023 937th Yax42 🇫🇷 822 73 9ms 12 Nov 2025 943rd snoozingnewt 🇨🇦 822 74 2,512ms 29 Nov 2025 944th KatieLG 🇬🇧 821 74 16ms 5 Nov 2020 944th trist224 🇫🇷 821 74 9ms 15 Nov 2022 944th QuincyNash 🇺🇸 821 74 9ms 29 Nov 2022 947th AaronGarbut 821 87 1ms 30 Jul 2019 948th MeWhenI 🇻🇦 820 98 38ms 28 Aug 2024 949th jared-hughes 819 154 1,691ms 16 Sep 2025 949th MeWhenI 🇻🇦 819 154 1,642ms 7 Nov 2025 951st phdphil 818 46 163ms 9 Apr 2018 952nd snoozingnewt 🇨🇦 818 68 144ms 29 Nov 2025 953rd dokutan 818 85 123ms 23 Jul 2025 954th orthoplex 🇨🇽 817 36 35ms 20 Jul 2024 955th Frank-Buss 817 93 5ms 29 Aug 2020 956th MeWhenI 🇻🇦 815 71 3ms 25 Jul 2023 957th NewDefectus 🇮🇱 814 54 14ms 15 Dec 2021 958th Waffle3z 814 58 38ms 20 Jan 2021 958th jbbarth 🇫🇷 814 58 34ms 8 Oct 2021 958th AlephSquirrel 814 58 44ms 14 Apr 2023 First Prev 881–960 of 3,221 Next Last