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?
Arrows 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 801st JunkIce 440 190 564ms 3 Dec 2024 802nd Andrey135296 440 217 12ms 17 Sep 2024 803rd CaedenHarper 🇨🇦 440 254 128ms 7 Nov 2025 804th CaedenHarper 🇨🇦 440 294 127ms 7 Nov 2025 805th yzhs 🇩🇪 440 338 190ms 6 Jun 2022 806th MiffOttah 439 193 14ms 6 Oct 2024 807th Yewzir 🇧🇪 439 288 3ms 18 Jan 2024 808th resoNathan 438 218 14ms 5 Jul 2024 809th henrytranter 436 219 14ms 1 Oct 2021 809th rschwa6308 🇺🇸 436 219 12ms 5 May 2023 809th yanjs 436 219 13ms 3 Jul 2025 812th perlebach 🇨🇿 435 149 4ms 3 Sep 2021 812th armin-k1 435 149 3ms 10 Sep 2021 814th mckymsh 435 195 14ms 4 Feb 2024 815th mdnestor 434 220 12ms 27 Dec 2022 816th elisherer 🇮🇱 433 196 11ms 28 Sep 2021 817th frosster 🇨🇦 433 216 2ms 19 Mar 2025 818th Yewzir 🇧🇪 433 260 627ms 24 Sep 2025 819th mokymok 🇺🇸 432 221 14ms 17 Nov 2021 819th hiichbindermax 432 221 12ms 5 Oct 2024 821st TRexOnGit 432 222 462ms 16 Jan 2024 821st SpareManiKatti 432 222 491ms 7 Apr 2025 823rd ian-h-chamberlain 🇺🇸 432 315 172ms 30 Jun 2022 824th madex 🇩🇪 429 302 98ms 13 days ago 825th tomh1012 428 198 14ms 23 Aug 2021 825th acollett89 428 198 13ms 5 Aug 2025 827th lovernj 428 223 15ms 21 Jan 2022 827th Ailko 🇧🇪 428 223 11ms 5 May 2022 827th karhuthebear 428 223 14ms 11 May 2022 827th andre-lameirinhas 🇵🇹 428 223 13ms 26 Apr 2023 827th anarconic 428 223 13ms 7 Dec 2023 827th ffelixm 428 223 12ms 4 Jun 2025 827th Andrey2001 428 223 14ms 25 Nov 2025 834th msbranicky 428 295 3ms 11 Aug 2023 835th msbranicky 428 318 268ms 3 Oct 2023 836th BREMAUCY 🇫🇷 427 262 160ms 29 Dec 2025 837th sergioabreu-g 427 319 234ms 20 Jun 2025 838th CatsAreFluffy 426 199 16ms 30 Dec 2022 838th alexsave 426 199 17ms 16 Oct 2025 840th SteveHales 426 208 113ms 20 Oct 2025 841st BobDotCom 426 224 14ms 25 Mar 2022 841st sleepyStick 426 224 13ms 14 Jul 2022 843rd Jacob385 426 264 655ms 28 Oct 2025 844th tamanugi 🇯🇵 426 304 123ms 4 Nov 2022 845th 1231234md5 🇨🇳 424 225 14ms 15 Dec 2023 845th billythegoat356 424 225 14ms 5 Jun 2024 847th CaedenHarper 🇨🇦 422 200 182ms 23 Aug 2025 848th pineapplebox 422 201 16ms 1 Apr 2022 849th trist224 🇫🇷 422 226 13ms 21 Feb 2023 850th TylerBloom 421 323 194ms 21 Mar 2024 851st Mabeloid 🇳🇴 420 199 505ms 18 Sep 2024 852nd abc7-12 420 205 2ms 2 Jun 2024 853rd mothcolada 🇺🇸 420 227 13ms 8 Oct 2021 853rd zt14427 420 227 14ms 28 Sep 2023 853rd ballaire 420 227 14ms 27 Jan 2024 853rd jatloe 420 227 14ms 23 Oct 2024 857th janAkali 🇷🇺 420 254 461ms 20 May 2024 858th cochrane 419 267 128ms 22 Mar 2024 859th gbxdl 419 325 192ms 19 Jul 2022 860th GeorgeStechman 🇬🇧 418 203 14ms 4 Dec 2023 860th smclaughlin-cf 418 203 13ms 6 May 2025 862nd tobyLovick 418 228 13ms 10 Dec 2023 862nd mathisfun271 418 228 12ms 6 Mar 2024 862nd Mefred 418 228 14ms 29 Oct 2025 865th MeWhenI 🇻🇦 417 148 49ms 15 Dec 2021 866th twocatsinatrenchcoat 417 229 13ms 14 Apr 2022 866th cthierfelder 🇲🇨 417 229 13ms 14 Nov 2025 866th tomh1012 417 229 11ms 18 Feb 2026 869th MeWhenI 🇻🇦 417 337 6ms 25 Nov 2023 870th EthanGrant1 415 230 14ms 10 Nov 2022 871st retrohun 415 257 379ms 24 days ago 872nd blaztoma 🇱🇹 415 304 4ms 9 Nov 2025 873rd zakariamouhid 414 205 13ms 22 Apr 2023 873rd Protothor 414 205 13ms 8 days ago 875th MichaelMBradley 🇨🇦 413 231 22ms 27 Feb 2022 875th Florian-Mt 413 231 11ms 27 Nov 2023 875th l-donovan 413 231 13ms 6 Feb 2024 878th hamhub7 413 232 481ms 9 Aug 2022 879th Ralac07 🇦🇺 412 206 15ms 24 Nov 2025 880th Attero 🇸🇪 412 209 2ms 5 Aug 2022 First Prev 801–880 of 1,330 Next Last