The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 7 days. Why not try and solve them ahead of time?
Day of Week 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 561st 386asm 🇺🇸 863 102 44ms 2 May 2023 562nd GrayJoKing 🇦🇺 862 55 130ms 18 Apr 2023 563rd brochmann 🇸🇪 862 76 23ms 13 Aug 2023 563rd bwenstar 862 76 24ms 21 Feb 2024 563rd sultan 862 76 22ms 26 Feb 2024 563rd xyangst 862 76 15ms 3 Oct 2024 563rd wh3n3v3r 🇨🇿 862 76 23ms 20 Nov 2024 563rd JunkIce 862 76 23ms 24 Nov 2024 569th jacobly0 🇺🇸 862 99 2ms 2 Oct 2023 569th kkoenig 862 99 2ms 28 Dec 2023 571st stefangimmillaro 861 69 421ms 13 Oct 2024 572nd HumanEquivalentUnit 860 70 16ms 28 Nov 2023 573rd edsrzf 🇳🇿 860 115 8ms 25 Jan 2026 573rd kg583 🇺🇸 860 115 7ms 25 Jan 2026 575th ovs-code 🇩🇪 860 143 468ms 14 Jul 2023 575th DialFrost 🇸🇬 860 143 488ms 31 Jan 2026 577th albanian-laundromat 859 71 406ms 4 Aug 2025 578th Steffan153 🇫🇮 859 103 58ms 23 Apr 2023 578th m-tkach 🇺🇦 859 103 58ms 23 Apr 2023 578th Lydxn 🇨🇦 859 103 61ms 26 May 2023 578th sean-niemann 🇺🇸 859 103 60ms 2 Nov 2023 578th DialFrost 🇸🇬 859 103 59ms 23 Dec 2024 578th edsrzf 🇳🇿 859 103 57ms 3 Jan 2026 584th kaascevich 859 145 694ms 22 Jul 2025 584th JayXon 🇺🇸 859 145 747ms 23 Jul 2025 586th dokutan 858 112 154ms 11 Nov 2025 586th DialFrost 🇸🇬 858 112 156ms 12 Feb 2026 588th primo-ppcg 🇹🇭 857 112 4ms 19 Apr 2023 588th saito-ta 🇯🇵 857 112 3ms 20 Apr 2023 590th erikgaal 855 51 5ms 5 Jan 2024 591st pardouin 🇫🇷 855 86 511ms 24 Sep 2025 591st kmathis22 855 86 521ms 7 Dec 2025 591st jkelly467 855 86 440ms 7 Jan 2026 594th edsrzf 🇳🇿 855 87 16ms 17 Oct 2025 594th kg583 🇺🇸 855 87 16ms 2 Nov 2025 596th AlephSquirrel 855 89 70ms 17 Apr 2023 596th GolfingSuccess 🇬🇷 855 89 69ms 26 Nov 2023 596th tobeannouncd 855 89 179ms 11 Jan 2024 596th ovs-code 🇩🇪 855 89 177ms 22 May 2024 596th lynn 855 89 162ms 8 Jan 2025 596th Natanaelel 🇸🇪 855 89 166ms 8 Jun 2025 596th emgordon154 855 89 82ms 16 Nov 2025 603rd GrayJoKing 🇦🇺 855 103 43ms 19 Apr 2023 604th snoozingnewt 🇨🇦 854 144 520ms 15 Dec 2025 605th kumavale 854 216 222ms 31 Dec 2025 606th postie77 853 69 384ms 17 Apr 2023 606th janbehrens 🇩🇪 853 69 388ms 15 May 2023 606th arctouch-cristiannevianna 853 69 375ms 18 May 2023 606th jwonagel 853 69 394ms 29 Sep 2023 606th apocriva 853 69 383ms 24 Nov 2023 606th markcahigyan 🇭🇺 853 69 379ms 7 Feb 2024 606th sultan 853 69 377ms 28 Feb 2024 606th Matto58 853 69 375ms 8 Nov 2024 606th TRexOnGit 853 69 390ms 28 Nov 2024 606th SpareManiKatti 853 69 399ms 7 Apr 2025 606th aliakseikalosha 853 69 374ms 17 Jan 2026 606th bpharaldsson 853 69 401ms 29 Jan 2026 618th Cube14yt 853 79 53ms 19 Nov 2025 619th DialFrost 🇸🇬 853 100 3ms 15 Feb 2026 620th Intevel 🇩🇪 853 125 295ms 4 Jul 2023 620th xnacly 🇩🇪 853 125 288ms 4 Jul 2023 620th msbranicky 853 125 302ms 31 Aug 2023 623rd MeWhenI 🇻🇦 852 52 1,471ms 17 Apr 2023 624th dokutan 851 70 212ms 7 Aug 2024 625th RaBa21 🇭🇺 851 77 15ms 19 Jul 2025 626th rucin93 🇵🇱 850 159 5ms 21 Apr 2025 626th edsrzf 🇳🇿 850 159 5ms 13 Feb 2026 628th DialFrost 🇸🇬 848 57 22ms 28 Feb 2025 629th MeWhenI 🇻🇦 846 102 9ms 6 Mar 2024 630th MeWhenI 🇻🇦 844 46 4ms 12 Aug 2024 631st stefangimmillaro 844 64 2,659ms 31 Oct 2024 631st emgordon154 844 64 2,572ms 30 Jan 2025 633rd grospolina 843 80 52ms 2 Oct 2024 634th Murphy4444 842 19 268ms 3 Dec 2025 635th ovs-code 🇩🇪 842 82 34ms 18 Oct 2025 636th Steffan153 🇫🇮 840 48 2ms 17 Apr 2023 636th clockworknazo 840 48 2ms 18 Apr 2023 636th primo-ppcg 🇹🇭 840 48 2ms 21 Apr 2023 636th sean-niemann 🇺🇸 840 48 2ms 21 Apr 2023 636th sisyphus-ppcg 🇦🇺 840 48 2ms 24 Apr 2023 First Prev 561–640 of 1,505 Next Last