The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 2 hours. 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 321st Shanethegamer 🇺🇸 912 86 461ms 15 May 2023 321st JayXon 🇺🇸 912 86 481ms 15 May 2023 321st Steffan153 🇫🇮 912 86 460ms 16 May 2023 321st Lydxn 🇨🇦 912 86 456ms 16 May 2023 321st GrayJoKing 🇦🇺 912 86 461ms 11 Aug 2023 321st sean-niemann 🇺🇸 912 86 468ms 11 Jul 2024 327th Bubbler-4 911 33 2,528ms 6 May 2022 327th rak1507 🇬🇧 911 33 108ms 8 May 2022 327th ngn 🇧🇬 911 33 25ms 11 May 2022 327th zacjl 911 33 32ms 3 Jun 2025 327th GrayJoKing 🇦🇺 911 33 13ms 4 Jun 2025 327th HPWiz 🇳🇿 911 33 9ms 16 Nov 2025 333rd Lydxn 🇨🇦 911 70 148ms 7 May 2022 333rd JayXon 🇺🇸 911 70 143ms 7 May 2022 335th Steffan153 🇫🇮 911 71 124ms 14 Oct 2022 335th Shanethegamer 🇺🇸 911 71 125ms 15 Oct 2022 335th stefangimmillaro 911 71 114ms 16 Oct 2022 335th MeWhenI 🇻🇦 911 71 118ms 16 Oct 2022 339th andersk 🇺🇸 911 91 139ms 25 Oct 2022 339th Super-Pizza 🇨🇦 911 91 128ms 4 Dec 2022 339th klixel 🇨🇦 911 91 126ms 20 May 2023 339th lynn 911 91 128ms 6 Jul 2024 339th edsrzf 🇳🇿 911 91 126ms 29 Nov 2024 339th DialFrost 🇸🇬 911 91 133ms 7 Apr 2025 339th elgan65536 🇺🇸 911 91 122ms 10 Feb 2026 339th fantaize 911 91 123ms 21 days ago 347th Lydxn 🇨🇦 910 47 257ms 5 May 2022 348th tailorspy 910 93 55ms 27 May 2024 348th sean-niemann 🇺🇸 910 93 60ms 9 Jun 2025 348th KasperKivimaeki 🇫🇮 910 93 63ms 26 Oct 2025 351st JayXon 🇺🇸 909 53 411ms 17 Aug 2024 352nd Lydxn 🇨🇦 909 81 39ms 1 Apr 2023 353rd Shanethegamer 🇺🇸 908 61 4ms 9 Oct 2023 354th nai62 908 68 7ms 27 Aug 2022 355th Steffan153 🇫🇮 908 73 68ms 26 Feb 2026 356th ovs-code 🇩🇪 908 75 67ms 12 Sep 2024 356th Kacarott 🇦🇺 908 75 62ms 13 Sep 2024 358th sean-niemann 🇺🇸 907 54 138ms 6 Aug 2024 358th Steffan153 🇫🇮 907 54 134ms 6 Aug 2024 358th lukegustafson 🇺🇸 907 54 139ms 7 Aug 2024 358th pardouin 🇫🇷 907 54 145ms 8 Aug 2024 358th Lydxn 🇨🇦 907 54 164ms 9 Aug 2024 363rd sean-niemann 🇺🇸 907 66 112ms 29 May 2025 364th lynn 907 78 1,231ms 5 May 2022 365th GrayJoKing 🇦🇺 905 71 321ms 10 Aug 2023 366th sean-niemann 🇺🇸 905 75 5ms 23 Dec 2025 366th Steffan153 🇫🇮 905 75 5ms 11 Feb 2026 368th primo-ppcg 🇹🇭 905 93 30ms 7 May 2022 368th AlephSquirrel 905 93 26ms 21 Jan 2023 368th kg583 🇺🇸 905 93 29ms 26 Dec 2024 368th CLOStrophobic 🇮🇹 905 93 30ms 17 Jan 2025 368th edsrzf 🇳🇿 905 93 30ms 3 Jul 2025 373rd JayXon 🇺🇸 905 105 291ms 4 Oct 2025 374th KrausRaus 🇺🇸 904 59 12ms 4 May 2022 374th voytxt 🇨🇿 904 59 10ms 4 May 2022 374th KingSkyrock 🇺🇸 904 59 11ms 18 May 2022 374th ZakkkkAttackkkk 🇵🇭 904 59 10ms 14 Jul 2022 374th aksyristos 904 59 11ms 28 Oct 2022 374th nstearns96 🇬🇧 904 59 11ms 28 Nov 2022 374th janbehrens 🇩🇪 904 59 10ms 17 May 2023 374th Shanethegamer 🇺🇸 904 59 11ms 25 May 2023 374th Maznek 904 59 10ms 26 Jun 2023 374th SpiritAxolotl 🇺🇸 904 59 10ms 20 Mar 2024 374th Andrey-Plotnikov 904 59 11ms 19 May 2024 374th emgordon154 904 59 11ms 5 Aug 2024 374th duckyluuk 🇳🇱 904 59 12ms 3 Oct 2024 374th lifthrasiir 🇰🇷 904 59 11ms 23 Nov 2024 374th fuzzylojik-golf 🇺🇸 904 59 11ms 1 Jun 2025 374th acollett89 904 59 12ms 17 Jun 2025 374th iczelia 🇩🇪 904 59 12ms 23 Sep 2025 374th Yax42 🇫🇷 904 59 10ms 20 Jan 2026 374th Protothor 904 59 11ms 4 days ago 393rd edsrzf 🇳🇿 903 72 128ms 3 Jul 2025 394th Shanethegamer 🇺🇸 903 77 14ms 15 May 2023 395th marshallward 🇺🇸 903 83 40ms 10 May 2022 396th krcs 🇵🇱 903 86 381ms 10 May 2022 396th billings7 🇬🇧 903 86 384ms 15 May 2022 396th revlayle 🇺🇸 903 86 379ms 7 Dec 2022 396th albanian-laundromat 903 86 430ms 30 Sep 2025 400th m-tkach 🇺🇦 903 90 31ms 7 Dec 2023 First Prev 321–400 of 3,628 Next Last