The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 2 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 151st twolfive 947 49 492ms 5 Oct 2024 151st sean-niemann 🇺🇸 947 49 517ms 3 Jun 2025 163rd GrayJoKing 🇦🇺 945 42 2ms 24 Mar 2021 163rd MeWhenI 🇻🇦 945 42 2ms 13 Mar 2025 165th Bubbler-4 945 72 134ms 20 Feb 2019 165th primo-ppcg 🇹🇭 945 72 145ms 9 Oct 2020 165th HPWiz 🇳🇿 945 72 140ms 15 Apr 2021 165th lynn 945 72 131ms 15 Apr 2021 165th JayXon 🇺🇸 945 72 139ms 28 Jun 2021 165th xnor-gate 945 72 137ms 22 Dec 2021 165th ovs-code 🇩🇪 945 72 136ms 4 Jul 2022 165th btnlq 945 72 139ms 15 Oct 2023 165th tobeannouncd 945 72 137ms 11 Jan 2024 174th janlelis 944 50 42ms 20 Sep 2021 175th kg583 🇺🇸 943 56 444ms 2 Mar 2024 175th JayXon 🇺🇸 943 56 398ms 2 Mar 2024 175th Steffan153 🇫🇮 943 56 408ms 3 Mar 2024 175th Lydxn 🇨🇦 943 56 420ms 3 Mar 2024 175th pardouin 🇫🇷 943 56 374ms 25 Jun 2024 175th emgordon154 943 56 422ms 22 Sep 2024 175th sean-niemann 🇺🇸 943 56 406ms 20 Feb 2025 175th fuzzylojik-golf 🇺🇸 943 56 450ms 4 Jan 2026 183rd sisyphus-ppcg 🇦🇺 943 67 4ms 2 Jul 2023 183rd Lydxn 🇨🇦 943 67 4ms 2 Jul 2023 183rd primo-ppcg 🇹🇭 943 67 5ms 3 Jul 2023 183rd Steffan153 🇫🇮 943 67 5ms 8 Aug 2024 183rd sean-niemann 🇺🇸 943 67 5ms 9 Jan 2025 183rd targrik 943 67 5ms 17 Jul 2025 189th nwellnhof 🇩🇪 943 108 281ms 17 Oct 2020 189th JayXon 🇺🇸 943 108 285ms 9 Jul 2021 189th Lydxn 🇨🇦 943 108 299ms 9 Jul 2021 189th MeWhenI 🇻🇦 943 108 293ms 4 Nov 2021 189th sisyphus-ppcg 🇦🇺 943 108 282ms 16 Mar 2022 189th stefangimmillaro 943 108 300ms 12 Jun 2023 189th edsrzf 🇳🇿 943 108 284ms 24 Feb 2026 196th saito-ta 🇯🇵 942 53 31ms 29 Jul 2024 197th JayXon 🇺🇸 942 78 381ms 21 Nov 2021 197th Lydxn 🇨🇦 942 78 395ms 21 Nov 2021 197th btnlq 942 78 368ms 10 Mar 2023 197th stefangimmillaro 942 78 360ms 15 Jul 2023 197th namelessiw 942 78 403ms 8 Aug 2024 202nd nwellnhof 🇩🇪 941 40 322ms 4 Oct 2020 203rd GrayJoKing 🇦🇺 941 53 1,296ms 13 Sep 2021 203rd Lydxn 🇨🇦 941 53 1,322ms 13 Sep 2021 203rd JayXon 🇺🇸 941 53 1,303ms 20 Sep 2021 203rd primo-ppcg 🇹🇭 941 53 1,295ms 22 Sep 2021 203rd sisyphus-ppcg 🇦🇺 941 53 1,237ms 3 Feb 2022 203rd Steffan153 🇫🇮 941 53 1,293ms 27 Mar 2023 203rd stefangimmillaro 941 53 1,328ms 14 Apr 2023 203rd pardouin 🇫🇷 941 53 1,270ms 13 Apr 2025 203rd sean-niemann 🇺🇸 941 53 1,193ms 13 Apr 2025 212th Bubbler-4 940 49 65ms 13 Sep 2023 212th GrayJoKing 🇦🇺 940 49 70ms 13 Sep 2023 212th Lydxn 🇨🇦 940 49 62ms 13 Sep 2023 212th ovs-code 🇩🇪 940 49 63ms 13 Sep 2023 212th Steffan153 🇫🇮 940 49 70ms 15 Sep 2023 212th primo-ppcg 🇹🇭 940 49 64ms 16 Sep 2023 212th Kacarott 🇦🇺 940 49 65ms 24 Nov 2023 212th error256 940 49 68ms 13 May 2024 212th pardouin 🇫🇷 940 49 64ms 24 Aug 2024 212th sean-niemann 🇺🇸 940 49 62ms 7 Apr 2025 212th DialFrost 🇸🇬 940 49 62ms 8 Apr 2025 223rd JayXon 🇺🇸 939 76 7ms 26 Nov 2021 224th sean-niemann 🇺🇸 937 89 431ms 24 Sep 2025 224th JayXon 🇺🇸 937 89 430ms 24 Sep 2025 224th nwellnhof 🇩🇪 937 89 451ms 25 Sep 2025 224th stefangimmillaro 937 89 472ms 6 Oct 2025 224th MeWhenI 🇻🇦 937 89 453ms 7 Nov 2025 224th DialFrost 🇸🇬 937 89 413ms 14 Nov 2025 224th h3ra993huskp 🇯🇵 937 89 491ms 30 Nov 2025 224th ScottHamper 937 89 451ms 30 Nov 2025 224th Lydxn 🇨🇦 937 89 426ms 12 Dec 2025 224th edsrzf 🇳🇿 937 89 511ms 25 Dec 2025 224th Steffan153 🇫🇮 937 89 397ms 11 Feb 2026 235th SnowballSH 935 65 10ms 31 Jan 2021 235th Larspolo 935 65 9ms 19 Jun 2021 235th jared-hughes 935 65 10ms 29 Oct 2021 235th falsidge 935 65 8ms 21 Jun 2023 235th Babafaba 935 65 10ms 5 Nov 2025 240th Lydxn 🇨🇦 935 87 120ms 13 Jan 2022 First Prev 161–240 of 3,221 Next Last