The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 3 hours. Why not try and solve them ahead of time?
Ordinal Numbers 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 481st primo-ppcg 🇹🇭 842 232 13ms 25 Jun 2025 482nd sean-niemann 🇺🇸 841 79 3ms 17 Jan 2024 482nd Steffan153 🇫🇮 841 79 3ms 29 Jan 2024 484th GrayJoKing 🇦🇺 841 109 22ms 24 Nov 2021 485th okhoel 🇳🇴 840 63 277ms 20 Sep 2022 486th primo-ppcg 🇹🇭 840 75 230ms 22 Oct 2020 487th neel11235813 839 68 420ms 27 Mar 2024 487th xsot 🇸🇬 839 68 398ms 14 May 2024 487th dokutan 839 68 371ms 3 days ago 490th GrayJoKing 🇦🇺 839 105 10ms 3 Mar 2026 491st Shanethegamer 🇺🇸 839 107 107ms 17 Dec 2021 492nd dsntzn 🇸🇰 838 76 11ms 29 Aug 2020 492nd GusGold 838 76 9ms 17 Nov 2020 494th GrayJoKing 🇦🇺 837 109 40ms 6 Sep 2022 495th boxjelly 837 135 181ms 2 Jan 2021 495th edsrzf 🇳🇿 837 135 177ms 21 Dec 2025 497th GolfingSuccess 🇬🇷 837 216 1,453ms 6 Mar 2025 498th SirBogman 🇺🇸 836 133 41ms 3 Jun 2025 499th GrayJoKing 🇦🇺 835 118 470ms 4 Mar 2022 500th DialFrost 🇸🇬 835 120 106ms 2 Dec 2025 501st GrayJoKing 🇦🇺 834 60 1,333ms 24 Mar 2021 502nd SirBogman 🇺🇸 834 76 13ms 20 Nov 2022 503rd inventshah 834 87 2ms 12 Jun 2022 504th MeWhenI 🇻🇦 833 59 7ms 18 Nov 2023 505th error256 833 84 12ms 22 Feb 2026 506th Steffan153 🇫🇮 833 95 5ms 20 Aug 2023 506th Shanethegamer 🇺🇸 833 95 5ms 20 Aug 2023 508th bendiscz 833 148 292ms 17 Apr 2020 508th sean-niemann 🇺🇸 833 148 305ms 29 Aug 2023 510th Shanethegamer 🇺🇸 833 217 1,426ms 28 Apr 2025 511th prplz 🇦🇺 832 53 64ms 7 Jun 2020 511th olivermrose 🇺🇸 832 53 37ms 4 Dec 2021 511th nwellnhof 🇩🇪 832 53 36ms 28 Dec 2021 511th JayXon 🇺🇸 832 53 38ms 22 Feb 2025 511th blaztoma 🇱🇹 832 53 39ms 2 days ago 516th kaascevich 832 108 106ms 20 Jul 2025 517th DaCoolOne 831 88 3ms 22 Feb 2022 518th MeWhenI 🇻🇦 830 80 4ms 13 Oct 2023 518th GolfingSuccess 🇬🇷 830 80 4ms 16 Nov 2023 520th MichalMarsalek 🇨🇿 828 107 422ms 8 Mar 2022 521st HumanEquivalentUnit 827 64 268ms 24 Jun 2020 521st bstrautin 827 64 367ms 20 Jul 2020 523rd GrayJoKing 🇦🇺 827 69 401ms 23 Jul 2024 523rd duckyluuk 🇳🇱 827 69 447ms 29 Aug 2024 523rd Shanethegamer 🇺🇸 827 69 377ms 30 Oct 2024 526th Andrey-Plotnikov 827 77 10ms 2 Jan 2023 526th Maznek 827 77 10ms 4 Jun 2023 526th Natanaelel 🇸🇪 827 77 12ms 18 Jan 2025 529th snyderek 🇺🇸 826 112 435ms 27 Sep 2024 530th DialFrost 🇸🇬 826 219 1,455ms 27 Jan 2025 531st stefangimmillaro 825 121 539ms 6 Oct 2025 532nd Sakisan 🇧🇪 825 137 180ms 12 Apr 2022 532nd Z-snails 825 137 176ms 5 Dec 2023 534th MeWhenI 🇻🇦 824 135 42ms 29 Apr 2025 535th MeWhenI 🇻🇦 823 82 10ms 29 Dec 2024 536th primo-ppcg 🇹🇭 823 99 385ms 21 Nov 2021 537th emplv 🇱🇻 822 150 292ms 30 Jun 2022 538th ovs-code 🇩🇪 822 220 1,451ms 1 Feb 2025 539th DialFrost 🇸🇬 820 81 4ms 2 Dec 2024 540th lynn 819 54 4ms 27 May 2022 541st btjones0 819 60 119ms 9 Jan 2021 541st janbehrens 🇩🇪 819 60 7ms 5 Dec 2023 543rd GrayJoKing 🇦🇺 819 85 175ms 31 May 2022 544th ovs-code 🇩🇪 819 113 443ms 3 Jun 2024 545th emplv 🇱🇻 818 92 122ms 20 Dec 2022 545th Steffan153 🇫🇮 818 92 2,602ms 13 Feb 2026 547th ScottHamper 818 122 546ms 30 Nov 2025 548th primo-ppcg 🇹🇭 817 90 19ms 28 Jan 2023 548th kg583 🇺🇸 817 90 19ms 20 Oct 2024 548th CLOStrophobic 🇮🇹 817 90 20ms 19 Jan 2025 551st stefangimmillaro 817 151 290ms 15 Jul 2023 552nd pg98 816 78 11ms 4 Sep 2019 552nd efgen 816 78 10ms 1 Jul 2020 552nd KaeruCT 816 78 10ms 7 Oct 2020 552nd ernestd 816 78 14ms 22 Jan 2021 552nd BambooleanLogic 🇸🇪 816 78 12ms 1 Dec 2021 552nd unfinishedprogram 816 78 9ms 29 Jun 2023 558th Attero 🇸🇪 815 51 186ms 21 Oct 2020 559th MeWhenI 🇻🇦 815 70 452ms 13 Jul 2024 560th sean-niemann 🇺🇸 815 73 7ms 20 Dec 2024 First Prev 481–560 of 1,895 Next Last