The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 4 days. Why not try and solve them ahead of time?
Happy Numbers 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 160th sean-niemann 🇺🇸 931 49 5ms 20 Feb 2025 162nd sean-niemann 🇺🇸 929 42 872ms 16 Sep 2025 162nd Steffan153 🇫🇮 929 42 726ms 14 Feb 2026 164th Lydxn 🇨🇦 929 52 2ms 10 Sep 2022 164th JayXon 🇺🇸 929 52 2ms 10 Sep 2022 164th btnlq 929 52 2ms 11 Sep 2022 167th lynn 929 54 13ms 15 Nov 2021 167th MeWhenI 🇻🇦 929 54 14ms 15 Nov 2021 167th Lydxn 🇨🇦 929 54 13ms 16 Nov 2021 167th GrayJoKing 🇦🇺 929 54 13ms 18 Nov 2021 167th btnlq 929 54 14ms 18 Nov 2021 167th annaproxy 929 54 15ms 5 Jan 2022 167th JayXon 🇺🇸 929 54 14ms 15 Feb 2022 167th Steffan153 🇫🇮 929 54 14ms 25 Sep 2022 167th IanUtley 929 54 13ms 17 Nov 2022 167th Yewzir 🇧🇪 929 54 14ms 11 Nov 2023 167th Betuaredead 929 54 14ms 12 Nov 2023 167th ovs-code 🇩🇪 929 54 14ms 30 Jun 2024 167th sean-niemann 🇺🇸 929 54 13ms 13 Apr 2025 167th DialFrost 🇸🇬 929 54 14ms 14 Apr 2025 167th snoozingnewt 🇨🇦 929 54 14ms 9 Dec 2025 182nd lukegustafson 🇺🇸 928 46 134ms 2 Sep 2024 182nd JayXon 🇺🇸 928 46 152ms 2 Sep 2024 184th Lydxn 🇨🇦 927 47 3ms 16 Jul 2023 185th Kacarott 🇦🇺 926 37 70ms 16 May 2024 186th MeWhenI 🇻🇦 926 43 4ms 22 Mar 2024 187th Babafaba 926 47 424ms 4 Nov 2025 188th Lydxn 🇨🇦 926 53 73ms 16 May 2022 188th GrayJoKing 🇦🇺 926 53 67ms 16 May 2022 188th Shanethegamer 🇺🇸 926 53 71ms 18 May 2022 188th Steffan153 🇫🇮 926 53 78ms 1 Oct 2022 188th JayXon 🇺🇸 926 53 70ms 20 Mar 2023 188th Yewzir 🇧🇪 926 53 72ms 9 Nov 2023 188th Betuaredead 926 53 70ms 13 Nov 2023 188th pardouin 🇫🇷 926 53 75ms 3 Sep 2024 188th sean-niemann 🇺🇸 926 53 69ms 18 Apr 2025 188th albanian-laundromat 926 53 71ms 8 Nov 2025 188th snoozingnewt 🇨🇦 926 53 71ms 6 Dec 2025 199th sean-niemann 🇺🇸 925 60 2ms 29 Oct 2022 199th Lydxn 🇨🇦 925 60 2ms 30 Oct 2022 199th sisyphus-ppcg 🇦🇺 925 60 2ms 3 Nov 2022 199th primo-ppcg 🇹🇭 925 60 4ms 19 Nov 2022 199th clockworknazo 925 60 4ms 19 Nov 2022 199th Steffan153 🇫🇮 925 60 2ms 28 Jan 2023 199th xsot 🇸🇬 925 60 2ms 25 Jul 2023 199th DialFrost 🇸🇬 925 60 4ms 14 Sep 2023 199th fuzzylojik-golf 🇺🇸 925 60 4ms 15 Sep 2025 199th canissimia 🇦🇶 925 60 2ms 16 Jan 2026 209th andersk 🇺🇸 925 68 120ms 22 Oct 2022 209th Steffan153 🇫🇮 925 68 132ms 16 Feb 2026 211th Frowny 924 51 9ms 3 Jul 2020 212th MeWhenI 🇻🇦 924 53 1,021ms 11 Nov 2021 212th HPWiz 🇳🇿 924 53 1,059ms 18 Mar 2022 212th Mukundan314 924 53 14ms 3 Jan 2026 215th JayXon 🇺🇸 922 55 1ms 9 Jul 2021 215th btnlq 922 55 1ms 28 Dec 2022 217th Lydxn 🇨🇦 922 56 37ms 14 Jun 2022 218th Lydxn 🇨🇦 921 59 110ms 14 Oct 2022 218th JayXon 🇺🇸 921 59 113ms 14 Oct 2022 218th MeWhenI 🇻🇦 921 59 116ms 17 Oct 2022 218th Steffan153 🇫🇮 921 59 128ms 9 Aug 2024 218th sean-niemann 🇺🇸 921 59 119ms 23 Dec 2024 223rd Steffan153 🇫🇮 920 56 72ms 13 Dec 2022 223rd MeWhenI 🇻🇦 920 56 72ms 13 Dec 2022 223rd Lydxn 🇨🇦 920 56 75ms 13 Dec 2022 223rd ovs-code 🇩🇪 920 56 71ms 21 Apr 2024 223rd DialFrost 🇸🇬 920 56 74ms 26 Dec 2024 223rd sean-niemann 🇺🇸 920 56 74ms 20 Feb 2025 223rd snoozingnewt 🇨🇦 920 56 77ms 3 Dec 2025 230th alo-gin 919 32 38ms 19 Oct 2018 231st JayXon 🇺🇸 919 53 2ms 32 hours ago 232nd Steffan153 🇫🇮 917 42 4ms 14 May 2023 233rd marcin7Cd 915 75 5ms 15 Feb 2021 233rd primo-ppcg 🇹🇭 915 75 5ms 1 Mar 2021 233rd kg583 🇺🇸 915 75 5ms 21 Oct 2024 233rd CLOStrophobic 🇮🇹 915 75 5ms 14 Feb 2025 233rd edsrzf 🇳🇿 915 75 5ms 11 Apr 2025 238th btnlq 915 80 1ms 11 Jun 2023 238th saito-ta 🇯🇵 915 80 1ms 11 Jun 2023 240th MeWhenI 🇻🇦 914 47 2,627ms 24 Oct 2024 First Prev 161–240 of 3,201 Next Last