The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 5 days. Why not try and solve them ahead of time?
Tutorial 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 856th dokutan 0 63 6ms 28 Apr 2025 856th Jigglypuffed 0 63 50ms 19 Jul 2025 856th penous 0 63 16ms 2 Aug 2025 856th YellowDudeIsMe 0 63 14ms 14 Aug 2025 856th albanian-laundromat 0 63 6ms 22 Aug 2025 856th snoozingnewt 🇨🇦 0 63 183ms 15 Sep 2025 856th snoozingnewt 🇨🇦 0 63 6ms 15 Sep 2025 856th snoozingnewt 🇨🇦 0 63 52ms 15 Sep 2025 856th luuumine 🇫🇷 0 63 2ms 10 Nov 2025 856th JOrE20 0 63 6ms 18 Nov 2025 856th kayaulai 0 63 93ms 23 Nov 2025 892nd Shanethegamer 🇺🇸 0 64 142ms 20 Nov 2024 892nd error256 0 64 131ms 21 Nov 2024 892nd error256 0 64 1,021ms 21 Nov 2024 892nd emgordon154 0 64 2ms 26 Nov 2024 892nd Liniarc 0 64 14ms 26 Nov 2024 892nd Natanaelel 🇸🇪 0 64 177ms 9 Dec 2024 892nd MeWhenI 🇻🇦 0 64 49ms 12 Dec 2024 892nd MeWhenI 🇻🇦 0 64 14ms 14 Feb 2025 892nd targrik 0 64 14ms 15 Feb 2025 892nd calum12345 0 64 14ms 25 Mar 2025 892nd sean-niemann 🇺🇸 0 64 74ms 30 Apr 2025 892nd TheDrawingCoder-Gamer 0 64 14ms 29 Jun 2025 892nd Babafaba 0 64 15ms 15 Oct 2025 892nd luuumine 🇫🇷 0 64 1,021ms 16 Oct 2025 892nd GolfingSuccess 🇬🇷 0 64 3ms 12 Nov 2025 892nd GolfingSuccess 🇬🇷 0 64 155ms 2 Dec 2025 892nd Shanethegamer 🇺🇸 0 64 152ms 4 Dec 2025 892nd GolfingSuccess 🇬🇷 0 64 110ms 15 Dec 2025 892nd amazingalek 🇳🇴 0 64 11ms 16 Dec 2025 892nd error256 0 64 150ms 3 Feb 2026 892nd pardouin 🇫🇷 0 64 167ms 4 Feb 2026 913th Shanethegamer 🇺🇸 0 65 8ms 20 Nov 2024 913th stefangimmillaro 0 65 10ms 20 Nov 2024 913th edsrzf 🇳🇿 0 65 10ms 21 Nov 2024 913th ovs-code 🇩🇪 0 65 12ms 25 Nov 2024 913th GolfingSuccess 🇬🇷 0 65 12ms 25 Nov 2024 913th AlephSquirrel 0 65 10ms 25 Nov 2024 913th AlephSquirrel 0 65 50ms 25 Nov 2024 913th pardouin 🇫🇷 0 65 11ms 25 Nov 2024 913th btnlq 0 65 10ms 26 Nov 2024 913th CaedenHarper 🇨🇦 0 65 12ms 26 Nov 2024 913th inventshah 0 65 11ms 26 Nov 2024 913th sean-niemann 🇺🇸 0 65 167ms 26 Nov 2024 913th stefangimmillaro 0 65 158ms 26 Nov 2024 913th duckyluuk 🇳🇱 0 65 10ms 26 Nov 2024 913th ovs-code 🇩🇪 0 65 2ms 26 Nov 2024 913th Alex-x90 🇺🇸 0 65 10ms 28 Nov 2024 913th zacjl 0 65 11ms 1 Dec 2024 913th zacjl 0 65 7ms 1 Dec 2024 913th sisyphus-ppcg 🇦🇺 0 65 12ms 2 Dec 2024 913th SirBogman 🇺🇸 0 65 11ms 3 Dec 2024 913th xsot 🇸🇬 0 65 11ms 4 Dec 2024 913th lukegustafson 🇺🇸 0 65 10ms 7 Dec 2024 913th Europe2048 0 65 13ms 7 Dec 2024 913th neel11235813 0 65 11ms 9 Dec 2024 913th Seek64 🇩🇪 0 65 11ms 10 Dec 2024 913th MeWhenI 🇻🇦 0 65 2ms 11 Dec 2024 913th antimon2 🇯🇵 0 65 11ms 16 Dec 2024 913th error256 0 65 6ms 16 Dec 2024 913th edsrzf 🇳🇿 0 65 7ms 18 Dec 2024 913th bizy-coder 0 65 11ms 28 Dec 2024 913th Bulmenisaurus 0 65 13ms 1 Jan 2025 913th m-tkach 🇺🇦 0 65 157ms 3 Jan 2025 913th emgordon154 0 65 7ms 11 Jan 2025 913th prplz 🇦🇺 0 65 11ms 23 Jan 2025 913th kg583 🇺🇸 0 65 6ms 23 Jan 2025 913th CLOStrophobic 🇮🇹 0 65 7ms 23 Jan 2025 913th mathisfun271 0 65 11ms 25 Jan 2025 913th Natanaelel 🇸🇪 0 65 11ms 26 Jan 2025 913th Shanethegamer 🇺🇸 0 65 11ms 30 Jan 2025 913th firegene 🇮🇪 0 65 10ms 30 Jan 2025 913th Lydxn 🇨🇦 0 65 10ms 31 Jan 2025 913th commandz0 🇺🇸 0 65 12ms 2 Feb 2025 913th GolfingSuccess 🇬🇷 0 65 6ms 3 Feb 2025 913th bricknellj 0 65 11ms 5 Feb 2025 913th qpwoeirut 0 65 4,462ms 7 Feb 2025 913th xyangst 0 65 13ms 14 Feb 2025 913th emgordon154 0 65 48ms 17 Feb 2025 913th acotis 0 65 297ms 18 Feb 2025 First Prev 881–960 of 3,404 Next Last