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 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 241st primo-ppcg 🇹🇭 818 307 11ms 3 Aug 2023 242nd nwellnhof 🇩🇪 817 140 59ms 6 May 2023 243rd Shanethegamer 🇺🇸 816 97 1,292ms 2 May 2023 244th plcc0 815 100 10ms 9 Oct 2025 245th WilliamDeBlieck 815 120 74ms 26 days ago 246th dokutan 814 81 1ms 7 Sep 2023 247th dokutan 814 93 409ms 13 days ago 248th the-zammers 814 158 122ms 10 Nov 2023 248th tobeannouncd 814 158 127ms 12 Jan 2024 250th Shanethegamer 🇺🇸 813 158 488ms 14 Jul 2023 251st JDiLenarda 🇫🇷 813 177 1,419ms 26 Jun 2025 252nd LukeBridges 🇬🇧 812 118 9ms 20 Sep 2024 252nd snoozingnewt 🇨🇦 812 118 10ms 31 Oct 2025 254th KasperKivimaeki 🇫🇮 811 141 71ms 2 Nov 2025 255th ScottHamper 811 164 500ms 30 Nov 2025 256th lynn 811 186 353ms 10 Nov 2025 257th edsrzf 🇳🇿 810 201 25ms 29 Apr 2025 258th Alessandro-Balconi 🇮🇹 809 121 80ms 1 May 2023 259th ovs-code 🇩🇪 809 135 14ms 1 Jul 2024 260th snoozingnewt 🇨🇦 809 136 101ms 5 Dec 2025 261st neel11235813 806 94 397ms 16 Jan 2024 262nd itsh01 806 119 9ms 1 May 2023 263rd Yewzir 🇧🇪 805 220 1,766ms 17 May 2024 264th sean-niemann 🇺🇸 804 195 281ms 29 Aug 2023 265th nwellnhof 🇩🇪 803 121 1ms 6 May 2023 266th emgordon154 801 322 1,463ms 9 Mar 2025 266th Shanethegamer 🇺🇸 801 322 1,820ms 14 Apr 2025 268th MeWhenI 🇻🇦 799 75 4ms 1 May 2023 269th sisyphus-ppcg 🇦🇺 798 131 6ms 23 Nov 2023 270th duckyluuk 🇳🇱 798 151 10ms 14 Jan 2025 271st DialFrost 🇸🇬 798 161 481ms 5 Jun 2024 272nd Steffan153 🇫🇮 796 197 33ms 9 May 2023 273rd kg583 🇺🇸 795 191 45ms 6 days ago 274th typeswitch-dev 🇵🇹 793 161 3ms 1 Sep 2023 275th albanian-laundromat 791 103 10ms 23 Apr 2025 276th edsrzf 🇳🇿 791 182 1,381ms 18 Jun 2025 277th nwellnhof 🇩🇪 790 124 408ms 10 May 2023 278th edsrzf 🇳🇿 789 78 34ms 2 Sep 2025 279th ovs-code 🇩🇪 789 145 62ms 3 Jun 2024 279th sean-niemann 🇺🇸 789 145 65ms 6 Jan 2026 281st edsrzf 🇳🇿 788 157 2ms 18 Jun 2025 282nd dylanarmstrong 786 122 9ms 23 Jan 2024 282nd two-bad 🇬🇧 786 122 10ms 24 Feb 2024 282nd Protothor 786 122 12ms 17 days ago 285th Shanethegamer 🇺🇸 786 161 394ms 3 May 2023 286th inventshah 783 167 2ms 11 Jan 2024 286th Yewzir 🇧🇪 783 167 2ms 19 Nov 2025 288th SirBogman 🇺🇸 782 197 41ms 3 Jun 2025 289th GrayJoKing 🇦🇺 781 141 6ms 23 days ago 290th stackotter 780 212 133ms 29 May 2023 291st albanian-laundromat 779 79 36ms 31 Oct 2025 292nd primo-ppcg 🇹🇭 778 54 39ms 5 May 2023 293rd SirBogman 🇺🇸 778 92 281ms 18 May 2024 294th emgordon154 777 127 2,720ms 28 Feb 2025 295th SirBogman 🇺🇸 776 87 32ms 4 Dec 2023 296th emgordon154 776 102 1,176ms 11 Aug 2024 297th FlorianCassayre 🇫🇷 776 105 17ms 24 Sep 2023 297th KatieLG 🇬🇧 776 105 9ms 25 May 2025 299th inventshah 773 148 463ms 27 Mar 2025 300th Steffan153 🇫🇮 772 117 3ms 27 Feb 2024 301st olleicua 🇺🇸 769 80 34ms 23 Mar 2024 302nd emgordon154 769 167 544ms 8 Feb 2026 303rd SirBogman 🇺🇸 768 71 2ms 4 Dec 2023 304th Steffan153 🇫🇮 766 128 403ms 9 Aug 2024 305th kg583 🇺🇸 766 162 4ms 2 Feb 2026 306th albanian-laundromat 765 99 390ms 4 Aug 2025 307th ovs-code 🇩🇪 765 127 1ms 16 Feb 2024 307th Steffan153 🇫🇮 765 127 1ms 17 Aug 2024 307th inventshah 765 127 1ms 27 Mar 2025 310th Shanethegamer 🇺🇸 765 205 29ms 9 May 2023 311th MeWhenI 🇻🇦 764 106 4ms 16 Aug 2024 312th wh3n3v3r 🇨🇿 762 107 10ms 13 Nov 2024 313th pardouin 🇫🇷 761 104 1,877ms 23 Jul 2025 314th helbling 🇨🇭 761 126 10ms 24 Sep 2024 315th edsrzf 🇳🇿 760 168 3ms 14 Oct 2025 316th pardouin 🇫🇷 759 81 65ms 30 Jul 2025 317th Natanaelel 🇸🇪 759 89 33ms 11 Feb 2024 318th sean-niemann 🇺🇸 759 128 2ms 6 Jan 2026 319th blaztoma 🇱🇹 759 145 124ms 1 Dec 2025 320th Shanethegamer 🇺🇸 759 148 165ms 24 May 2025 First Prev 241–320 of 853 Next Last