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 237th CaedenHarper 🇨🇦 834 137 11ms 11 Aug 2025 237th Flekay 🇩🇪 834 137 19ms 19 Feb 2026 237th snoozingnewt 🇨🇦 834 137 10ms 20 Feb 2026 237th dokutan 834 137 10ms 13 days ago 237th aksyristos 834 137 10ms 4 hours ago 246th edsrzf 🇳🇿 834 168 2ms 26 Jul 2025 247th voytxt 🇨🇿 833 134 15ms 26 Nov 2025 248th ovs-code 🇩🇪 833 145 62ms 3 Jun 2024 248th sean-niemann 🇺🇸 833 145 65ms 6 Jan 2026 250th albanian-laundromat 833 336 1,492ms 24 Oct 2025 251st nwellnhof 🇩🇪 832 121 1ms 6 May 2023 252nd emgordon154 831 102 1,176ms 11 Aug 2024 253rd jared-hughes 830 283 8ms 7 Jul 2024 254th snoozingnewt 🇨🇦 829 138 101ms 5 Dec 2025 255th edsrzf 🇳🇿 829 147 3ms 22 Nov 2025 256th m-tkach 🇺🇦 828 117 515ms 21 Jan 2024 256th b-illy 🇬🇧 828 117 480ms 14 Jun 2025 258th Shanethegamer 🇺🇸 828 159 495ms 14 Jul 2023 259th Steffan153 🇫🇮 827 128 403ms 9 Aug 2024 260th tayloia 🇬🇧 827 135 10ms 2 May 2023 260th thisishowmymindworks 🇳🇴 827 135 10ms 6 Jun 2023 260th jared-hughes 827 135 9ms 28 Jul 2023 260th Argeento 🇵🇱 827 135 9ms 8 Sep 2023 260th Andrey-Plotnikov 827 135 11ms 26 Sep 2025 260th Lv0Sys 🇵🇱 827 135 10ms 8 Dec 2025 266th the-zammers 827 160 122ms 10 Nov 2023 266th tobeannouncd 827 160 127ms 12 Jan 2024 268th stefangimmillaro 827 164 674ms 6 Oct 2025 268th ScottHamper 827 164 500ms 30 Nov 2025 270th Waffle3z 826 155 1ms 14 Sep 2023 270th edsrzf 🇳🇿 826 155 2ms 22 Aug 2025 272nd lynn 826 210 353ms 10 Nov 2025 273rd albanian-laundromat 824 83 36ms 31 Oct 2025 274th edsrzf 🇳🇿 824 201 25ms 29 Apr 2025 275th primo-ppcg 🇹🇭 824 331 11ms 3 Aug 2023 276th emgordon154 822 139 9ms 19 May 2025 277th sisyphus-ppcg 🇦🇺 821 131 6ms 23 Nov 2023 278th DialFrost 🇸🇬 821 136 10ms 14 Jan 2024 279th Shanethegamer 🇺🇸 821 156 1ms 5 May 2023 280th alemelis 817 106 1,088ms 5 Oct 2024 281st DialFrost 🇸🇬 817 128 23ms 1 Mar 2025 282nd ahmetdemirag 🇨🇾 817 140 10ms 30 Oct 2024 282nd InigoK 🇺🇸 817 140 10ms 10 Sep 2025 284th duckyluuk 🇳🇱 816 151 10ms 14 Jan 2025 285th CaedenHarper 🇨🇦 815 137 14ms 23 Aug 2025 286th sean-niemann 🇺🇸 815 196 273ms 28 Aug 2023 287th olleicua 🇺🇸 814 84 34ms 13 May 2025 288th Steffan153 🇫🇮 814 119 470ms 17 Jan 2024 289th DialFrost 🇸🇬 813 162 490ms 5 Jun 2024 290th kg583 🇺🇸 812 191 45ms 6 days ago 291st rschwa6308 🇺🇸 811 141 16ms 5 May 2023 291st zbreit 🇺🇸 811 141 17ms 5 May 2023 291st neel11235813 811 141 9ms 25 Oct 2023 291st MeWhenI 🇻🇦 811 141 11ms 26 Feb 2025 295th Shanethegamer 🇺🇸 811 161 394ms 3 May 2023 296th typeswitch-dev 🇵🇹 810 161 3ms 1 Sep 2023 297th JDiLenarda 🇫🇷 810 181 1,419ms 26 Jun 2025 298th Steffan153 🇫🇮 810 197 33ms 9 May 2023 299th WilliamDeBlieck 809 128 77ms 26 days ago 300th Irratix 🇳🇱 809 138 9ms 27 May 2023 301st emgordon154 809 346 1,463ms 9 Mar 2025 301st Shanethegamer 🇺🇸 809 346 1,820ms 14 Apr 2025 303rd ericlangedijk 🇸🇮 808 131 417ms 22 May 2023 304th edsrzf 🇳🇿 806 182 1,381ms 18 Jun 2025 305th GolfingSuccess 🇬🇷 805 142 10ms 1 May 2023 305th janbehrens 🇩🇪 805 142 10ms 1 May 2023 305th MichalMarsalek 🇨🇿 805 142 10ms 1 May 2023 305th inventshah 805 142 10ms 3 May 2023 305th doktoren 805 142 10ms 7 Dec 2023 305th anter69 🇭🇺 805 142 10ms 7 Oct 2024 305th roguh 🇬🇹 805 142 9ms 15 Oct 2024 305th KasperKivimaeki 🇫🇮 805 142 9ms 2 Nov 2025 313th SirBogman 🇺🇸 804 87 32ms 4 Dec 2023 314th JOrE20 804 139 11ms 22 Feb 2026 315th edsrzf 🇳🇿 804 200 44ms 7 Apr 2025 316th rucin93 🇵🇱 803 133 152ms 21 Feb 2025 317th GrayJoKing 🇦🇺 803 143 6ms 23 days ago 318th revlayle 🇺🇸 802 132 407ms 7 Jun 2023 318th AdrienHache 🇫🇷 802 132 424ms 28 Dec 2024 320th SirBogman 🇺🇸 801 73 2ms 4 Dec 2023 First Prev 241–320 of 857 Next Last