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?
Arrows 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 801st bobbysq 495 146 13ms 10 May 2023 801st ValentinCassayre 495 146 14ms 18 Oct 2023 801st BREMAUCY 🇫🇷 495 146 10ms 26 Dec 2025 804th crizin 🇰🇷 493 220 661ms 15 Sep 2023 805th TylerBloom 493 275 194ms 21 Mar 2024 806th msbranicky 492 247 3ms 11 Aug 2023 807th setop 491 147 14ms 18 Aug 2023 807th yanjs 491 147 13ms 3 Jul 2025 809th MeWhenI 🇻🇦 490 185 129ms 25 May 2022 810th gbxdl 489 277 192ms 19 Jul 2022 811th PyryL 🇫🇮 488 148 12ms 21 Aug 2024 812th madex 🇩🇪 488 249 3ms 17 days ago 813th msbranicky 487 173 2ms 10 Oct 2023 814th premun 🇨🇿 487 183 497ms 19 Nov 2022 815th BREMAUCY 🇫🇷 486 208 428ms 26 Dec 2025 816th mokymok 🇺🇸 485 149 14ms 17 Nov 2021 816th QuincyNash 🇺🇸 485 149 13ms 6 Dec 2022 816th CheeseCake628 🇳🇴 485 149 23ms 22 Jan 2023 819th KatieLG 🇬🇧 485 187 128ms 8 Nov 2025 820th janbehrens 🇩🇪 484 122 4ms 10 Jul 2023 821st hamhub7 484 184 481ms 9 Aug 2022 821st ChrisTheisen 484 184 486ms 14 Dec 2022 823rd madex 🇩🇪 484 209 390ms 17 days ago 824th retrohun 484 298 4ms 15 Nov 2025 825th DrPrettyman 482 150 14ms 12 Jul 2023 826th lovernj 478 151 15ms 21 Jan 2022 826th Ailko 🇧🇪 478 151 11ms 5 May 2022 826th karhuthebear 478 151 14ms 11 May 2022 826th andre-lameirinhas 🇵🇹 478 151 13ms 26 Apr 2023 826th anarconic 478 151 13ms 7 Dec 2023 826th ffelixm 478 151 12ms 4 Jun 2025 832nd trinityy-7 478 171 14ms 17 Jul 2023 833rd janbehrens 🇩🇪 477 138 335ms 1 Nov 2021 834th tomh1012 477 212 402ms 11 hours ago 835th aliakseikalosha 476 187 487ms 7 Aug 2023 836th SirFireball3521 475 152 45ms 25 Jan 2023 837th Bonjour27891 🇻🇳 472 153 13ms 4 Mar 2022 837th 1231234md5 🇨🇳 472 153 14ms 15 Dec 2023 837th billythegoat356 472 153 14ms 5 Jun 2024 840th con-cs 472 173 12ms 17 Oct 2021 840th Larento 472 173 16ms 14 Oct 2023 842nd wiebecommajonas 472 287 191ms 31 Oct 2021 843rd ericlangedijk 🇸🇮 471 189 445ms 12 Mar 2022 844th JGDoerrer 471 288 196ms 14 Jan 2022 845th CaedenHarper 🇨🇦 470 122 43ms 24 Aug 2025 846th Chinay-Domitrix 🇺🇸 470 192 2,768ms 4 Nov 2025 847th yzhs 🇩🇪 469 154 25ms 6 Nov 2021 848th Mabeloid 🇳🇴 469 173 2ms 20 Oct 2025 849th KingSkyrock 🇺🇸 469 174 14ms 16 Feb 2022 850th funnsam 🇭🇰 469 289 203ms 23 Oct 2023 851st tomh1012 467 260 3ms 7 hours ago 852nd mothcolada 🇺🇸 466 155 13ms 8 Oct 2021 852nd CatsAreFluffy 466 155 13ms 30 Dec 2022 852nd zt14427 466 155 14ms 28 Sep 2023 852nd ridingqwerty 🇺🇸 466 155 14ms 13 Dec 2023 852nd ballaire 466 155 14ms 27 Jan 2024 852nd jatloe 466 155 14ms 23 Oct 2024 858th Adix-null 🇱🇹 466 191 463ms 25 Feb 2023 859th Natanaelel 🇸🇪 464 131 46ms 7 Feb 2024 860th Ailko 🇧🇪 464 134 267ms 12 May 2022 861st adamnielson42 🇺🇸 464 176 11ms 30 May 2023 862nd commandz0 🇺🇸 463 143 741ms 1 Sep 2025 863rd amollberg 🇸🇪 463 156 12ms 8 Jan 2022 863rd Just4FunCoder 463 156 14ms 18 Jun 2025 865th Shanethegamer 🇺🇸 461 76 5ms 25 Apr 2022 866th ollyspooner 461 177 13ms 25 Nov 2022 866th Re-Adventures 🇮🇳 461 177 14ms 17 Dec 2023 866th hacker112 🇸🇪 461 177 14ms 19 Jun 2024 869th ian-h-chamberlain 🇺🇸 461 294 191ms 30 Jun 2022 870th Andrey135296 460 157 12ms 17 Sep 2024 870th cthierfelder 🇲🇨 460 157 13ms 14 Nov 2025 872nd madex 🇩🇪 460 242 130ms 17 days ago 873rd Salutations45 459 178 13ms 21 Dec 2024 874th Fishron 457 158 15ms 13 Jun 2022 874th EthanGrant1 457 158 14ms 10 Nov 2022 876th null-tangent 456 179 14ms 23 Aug 2022 877th Just4FunCoder 455 126 41ms 18 Jun 2025 878th Daniikk1012 454 134 38ms 3 Nov 2025 879th henrytranter 454 159 14ms 1 Oct 2021 879th MichaelMBradley 🇨🇦 454 159 22ms 27 Feb 2022 First Prev 801–880 of 1,332 Next Last