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?
Forsyth–Edwards Notation 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 321st kg583 🇺🇸 800 121 410ms 6 Feb 2026 321st sean-niemann 🇺🇸 800 121 496ms 6 Feb 2026 323rd mtirado1 800 160 1ms 1 May 2023 324th pardouin 🇫🇷 799 106 1,877ms 23 Jul 2025 325th davecame 799 143 16ms 30 Nov 2023 325th stefangimmillaro 799 143 11ms 23 May 2025 327th emgordon154 798 166 8ms 7 Jan 2025 328th emgordon154 796 129 2,720ms 28 Feb 2025 329th SirBogman 🇺🇸 794 144 10ms 1 May 2023 329th cros107 🇦🇺 794 144 10ms 26 Oct 2023 331st Yewzir 🇧🇪 793 244 1,766ms 17 May 2024 332nd Shanethegamer 🇺🇸 792 107 1,239ms 1 May 2023 333rd Steffan153 🇫🇮 792 127 1ms 17 Aug 2024 334th quirked-up 792 141 10ms 31 Aug 2023 334th KrausRaus 🇺🇸 792 141 10ms 3 Nov 2023 336th MeWhenI 🇻🇦 792 177 2ms 1 May 2023 337th Steffan153 🇫🇮 791 154 3ms 23 Jun 2023 338th kg583 🇺🇸 791 162 4ms 2 Feb 2026 339th RockOfStone 790 162 1ms 4 Nov 2025 340th blaztoma 🇱🇹 789 145 124ms 1 Dec 2025 341st NerdyMcNerd42 788 145 10ms 13 May 2023 341st mathisfun271 788 145 9ms 18 Feb 2024 341st neihousaigaai 788 145 11ms 10 Apr 2025 344th SirBogman 🇺🇸 788 199 41ms 3 Jun 2025 345th DialFrost 🇸🇬 787 110 321ms 14 Jan 2024 346th duckyluuk 🇳🇱 787 123 474ms 27 Mar 2024 347th LukeBridges 🇬🇧 787 142 9ms 20 Sep 2024 348th Natanaelel 🇸🇪 786 89 33ms 11 Feb 2024 349th MeWhenI 🇻🇦 786 106 4ms 16 Aug 2024 350th ovs-code 🇩🇪 786 128 2ms 16 Feb 2024 350th sean-niemann 🇺🇸 786 128 2ms 6 Jan 2026 352nd emgordon154 784 168 577ms 8 Jun 2025 353rd GolfingSuccess 🇬🇷 783 113 7ms 1 May 2023 354th Shanethegamer 🇺🇸 781 124 495ms 16 Jan 2024 355th itsh01 781 143 9ms 1 May 2023 356th 2bular 780 75 2ms 11 Nov 2025 357th GolfingSuccess 🇬🇷 779 107 4ms 18 Aug 2024 358th Shanethegamer 🇺🇸 779 150 165ms 24 May 2025 359th inventshah 779 155 465ms 1 May 2023 360th Shanethegamer 🇺🇸 779 180 2ms 5 May 2023 361st annaproxy 778 136 414ms 22 May 2023 362nd commandz0 🇺🇸 778 147 16ms 1 May 2023 362nd SniperSmiley 🇺🇸 778 147 10ms 15 Aug 2023 362nd fourth-bit 778 147 16ms 2 Jul 2024 365th Shanethegamer 🇺🇸 778 205 29ms 9 May 2023 366th edsrzf 🇳🇿 776 168 3ms 14 Oct 2025 367th DialFrost 🇸🇬 773 108 1,093ms 31 Aug 2025 367th CaedenHarper 🇨🇦 773 108 1,115ms 16 Sep 2025 369th Shanethegamer 🇺🇸 773 137 409ms 26 Mar 2024 370th edsrzf 🇳🇿 773 155 63ms 27 Jul 2025 371st RDShah 772 148 10ms 3 May 2023 371st knutae 🇳🇴 772 148 9ms 13 Nov 2023 371st qpwoeirut 772 148 10ms 19 Sep 2025 374th lifthrasiir 🇰🇷 770 76 2ms 6 Dec 2024 374th emgordon154 770 76 2ms 8 Jun 2025 376th DialFrost 🇸🇬 770 182 2ms 14 Sep 2024 377th lifthrasiir 🇰🇷 769 126 646ms 2 Dec 2024 378th Shanethegamer 🇺🇸 768 140 4ms 2 May 2023 379th Shanethegamer 🇺🇸 768 174 5ms 4 Oct 2024 380th MeWhenI 🇻🇦 767 73 42ms 1 May 2023 381st MeWhenI 🇻🇦 767 138 417ms 26 Jul 2023 382nd scpchicken 🇵🇼 767 149 10ms 1 May 2023 382nd Emutis 🇱🇹 767 149 10ms 26 Oct 2025 382nd plcc0 767 149 29ms 15 Feb 2026 385th DialFrost 🇸🇬 766 159 3ms 14 Jan 2024 386th sean-niemann 🇺🇸 766 169 40ms 9 Dec 2023 387th dylanarmstrong 765 146 9ms 23 Jan 2024 387th two-bad 🇬🇧 765 146 10ms 24 Feb 2024 387th Protothor 765 146 12ms 17 days ago 390th GrayJoKing 🇦🇺 763 209 27ms 24 May 2023 391st emplv 🇱🇻 761 210 292ms 6 May 2023 392nd stefangimmillaro 760 135 2,749ms 14 Nov 2024 393rd Shanethegamer 🇺🇸 759 114 293ms 9 May 2023 394th CaedenHarper 🇨🇦 757 128 498ms 11 Aug 2025 394th dokutan 757 128 438ms 13 days ago 396th Anonymousellama21 757 151 10ms 9 Aug 2024 397th janbehrens 🇩🇪 757 174 514ms 1 May 2023 398th edsrzf 🇳🇿 757 211 288ms 16 Apr 2025 399th stefangimmillaro 757 229 191ms 4 Jun 2025 400th stackotter 756 222 325ms 29 May 2023 First Prev 321–400 of 857 Next Last