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?
Collatz 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 157th Salutations45 933 58 5ms 18 Dec 2024 157th canissimia 🇦🇶 933 58 5ms 12 Dec 2025 163rd ovs-code 🇩🇪 932 60 19ms 4 May 2022 163rd m-tkach 🇺🇦 932 60 18ms 4 May 2022 163rd btnlq 932 60 25ms 5 May 2022 163rd orthoplex 🇨🇽 932 60 24ms 9 Oct 2022 163rd FlorianCassayre 🇫🇷 932 60 19ms 7 Nov 2022 163rd SirBogman 🇺🇸 932 60 20ms 20 Nov 2022 163rd QuincyNash 🇺🇸 932 60 20ms 1 Dec 2022 163rd Steffan153 🇫🇮 932 60 19ms 19 Dec 2022 163rd SirFireball3521 932 60 17ms 26 Jan 2023 163rd Shanethegamer 🇺🇸 932 60 20ms 25 May 2023 163rd CornerMercury 🇬🇧 932 60 20ms 19 Jun 2023 163rd ndren 932 60 21ms 2 Aug 2023 163rd kg583 🇺🇸 932 60 48ms 14 Aug 2023 163rd Just4FunCoder 932 60 21ms 17 Feb 2024 163rd HumanoidCPU 932 60 20ms 6 May 2024 163rd sean-niemann 🇺🇸 932 60 19ms 10 Jul 2024 163rd pardouin 🇫🇷 932 60 17ms 11 Jul 2024 163rd dokutan 932 60 20ms 15 Aug 2024 163rd jatloe 932 60 20ms 26 Aug 2024 163rd emgordon154 932 60 20ms 6 Sep 2024 163rd starfihs 932 60 18ms 12 Oct 2024 163rd CaedenHarper 🇨🇦 932 60 20ms 3 Nov 2024 163rd 5quiwyrm 932 60 18ms 12 Nov 2024 163rd plcc0 932 60 16ms 26 Mar 2025 163rd yujh-yujh 🇬🇸 932 60 18ms 28 Mar 2025 163rd albanian-laundromat 932 60 19ms 12 Apr 2025 163rd Mukundan314 932 60 22ms 17 Apr 2025 163rd fuzzylojik-golf 🇺🇸 932 60 20ms 1 Sep 2025 163rd luuumine 🇫🇷 932 60 20ms 3 Nov 2025 163rd Babafaba 932 60 18ms 7 Nov 2025 163rd hellopir2 932 60 20ms 24 Nov 2025 194th canissimia 🇦🇶 931 51 1,302ms 6 May 2022 194th Lydxn 🇨🇦 931 51 1,280ms 6 May 2022 194th primo-ppcg 🇹🇭 931 51 1,309ms 6 May 2022 194th pardouin 🇫🇷 931 51 1,391ms 12 Apr 2025 198th grey0ut 930 48 2,086ms 8 Apr 2025 199th JayXon 🇺🇸 930 73 4ms 23 Dec 2025 200th m-tkach 🇺🇦 930 91 61ms 5 May 2022 200th 09cf 930 91 56ms 4 Oct 2023 202nd GolfingSuccess 🇬🇷 927 49 38ms 12 Aug 2024 202nd Shanethegamer 🇺🇸 927 49 39ms 12 Aug 2024 202nd Steffan153 🇫🇮 927 49 39ms 12 Aug 2024 202nd MeWhenI 🇻🇦 927 49 37ms 13 Aug 2024 202nd DialFrost 🇸🇬 927 49 38ms 13 Aug 2024 202nd GrayJoKing 🇦🇺 927 49 41ms 15 Aug 2024 202nd btnlq 927 49 39ms 16 Aug 2024 202nd emgordon154 927 49 41ms 19 Aug 2024 202nd ovs-code 🇩🇪 927 49 39ms 19 Aug 2024 202nd mousetail 🇳🇱 927 49 39ms 13 Sep 2024 202nd lynn 927 49 39ms 20 Dec 2024 202nd weeble 927 49 40ms 20 Dec 2024 202nd sean-niemann 🇺🇸 927 49 39ms 11 Jan 2025 215th ovs-code 🇩🇪 927 52 455ms 16 Jan 2024 215th kg583 🇺🇸 927 52 410ms 24 Jan 2024 215th Shanethegamer 🇺🇸 927 52 407ms 24 Mar 2024 215th pardouin 🇫🇷 927 52 408ms 11 Jul 2024 215th Steffan153 🇫🇮 927 52 401ms 17 Aug 2024 215th sean-niemann 🇺🇸 927 52 479ms 24 Jan 2025 221st emplv 🇱🇻 927 60 10ms 5 May 2022 221st GrayJoKing 🇦🇺 927 60 9ms 6 May 2022 221st targrik 927 60 9ms 24 Dec 2024 221st xsot 🇸🇬 927 60 10ms 1 May 2025 225th Lydxn 🇨🇦 926 38 1,544ms 4 May 2022 225th GrayJoKing 🇦🇺 926 38 373ms 5 May 2022 225th Steffan153 🇫🇮 926 38 368ms 16 Dec 2022 225th ovs-code 🇩🇪 926 38 371ms 30 Dec 2023 229th MeWhenI 🇻🇦 925 68 98ms 23 Feb 2023 229th JayXon 🇺🇸 925 68 107ms 4 Mar 2025 231st JayXon 🇺🇸 924 53 161ms 24 Feb 2026 232nd Lydxn 🇨🇦 924 70 110ms 17 Oct 2022 232nd JayXon 🇺🇸 924 70 120ms 17 Oct 2022 234th roavin 924 84 361ms 23 Jun 2022 234th tkr-sh 🇰🇵 924 84 369ms 20 Aug 2022 234th Nickmiste 924 84 364ms 9 Nov 2022 234th postie77 924 84 369ms 19 May 2023 234th ertz1ertz 924 84 377ms 13 Sep 2024 234th Grabnukebomb 924 84 366ms 13 Sep 2024 234th Shanethegamer 🇺🇸 924 84 388ms 9 Apr 2025 First Prev 161–240 of 3,621 Next Last