The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 6 days. Why not try and solve them ahead of time?
ROT13 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 400th bricknellj 809 70 11ms 30 Oct 2025 402nd stefangimmillaro 809 135 275ms 2 Jan 2025 403rd aksyristos 808 41 36ms 7 Jan 2025 403rd CornerMercury 🇬🇧 808 41 36ms 17 Jan 2025 403rd HumanoidCPU 808 41 37ms 1 Feb 2025 403rd dokutan 808 41 37ms 4 Feb 2025 403rd CaedenHarper 🇨🇦 808 41 36ms 7 Sep 2025 403rd prestosilver 🇺🇸 808 41 35ms 18 Nov 2025 409th CLOStrophobic 🇮🇹 808 115 15ms 19 Jan 2025 409th kg583 🇺🇸 808 115 17ms 24 Feb 2026 411th GolfingSuccess 🇬🇷 806 104 451ms 31 Jan 2026 412th Yax42 🇫🇷 803 89 406ms 18 Feb 2026 413th bizy-coder 803 103 10ms 2 Jan 2025 413th DialFrost 🇸🇬 803 103 11ms 2 Jan 2025 413th Shanethegamer 🇺🇸 803 103 10ms 6 Jan 2025 413th XenThe 🇬🇧 803 103 13ms 1 Jul 2025 413th trinityy-7 803 103 11ms 21 Jul 2025 418th kaascevich 803 114 103ms 29 Jul 2025 419th sean-niemann 🇺🇸 803 136 295ms 3 Jan 2025 420th adriweb 🇫🇷 802 105 2ms 8 Jan 2025 420th FlyingPenguin223 802 105 2ms 7 Mar 2025 420th frosster 🇨🇦 802 105 3ms 6 Feb 2026 423rd kg583 🇺🇸 801 88 7ms 15 Feb 2026 424th MeWhenI 🇻🇦 801 98 29ms 25 Nov 2025 425th AlephSquirrel 801 116 16ms 5 Jan 2025 426th tatzyr 🇯🇵 800 63 2,138ms 29 Jul 2025 427th stefangimmillaro 800 105 374ms 7 Oct 2025 428th Shanethegamer 🇺🇸 798 71 11ms 2 Jan 2025 428th aksyristos 798 71 11ms 3 Jan 2025 428th voytxt 🇨🇿 798 71 11ms 3 Jan 2025 428th maxgodfrey2004 🇨🇦 798 71 11ms 4 Jan 2025 428th mrmena 🇦🇺 798 71 11ms 5 Jan 2025 428th croc54 798 71 11ms 5 Jan 2025 428th nstearns96 🇬🇧 798 71 11ms 6 Jan 2025 428th rollershutter 798 71 11ms 6 Jan 2025 428th moustave 798 71 11ms 7 Jan 2025 428th jmerle 🇳🇱 798 71 10ms 7 Jan 2025 428th NickTheEASDude 🇺🇸 798 71 11ms 8 Jan 2025 428th btjones0 798 71 10ms 11 Jan 2025 428th psaban 798 71 11ms 12 Jan 2025 428th scpchicken 🇵🇼 798 71 10ms 13 Jan 2025 428th neihousaigaai 798 71 10ms 13 Jan 2025 428th DGipe 798 71 11ms 13 Jan 2025 428th hiichbindermax 798 71 10ms 14 Jan 2025 428th rschwa6308 🇺🇸 798 71 11ms 14 Jan 2025 428th ImpressedByRocks 798 71 29ms 17 Jan 2025 428th primo-ppcg 🇹🇭 798 71 10ms 21 Jan 2025 428th davecame 798 71 11ms 29 Jan 2025 428th andrewjc2000 798 71 11ms 28 Feb 2025 428th Pyroan 798 71 10ms 7 Mar 2025 428th Troon 798 71 11ms 14 Mar 2025 428th souta-1326 798 71 10ms 25 Mar 2025 428th connor-grady 798 71 11ms 18 May 2025 428th bknower 798 71 11ms 30 Jun 2025 428th muser-logiccpu 🇺🇦 798 71 11ms 24 Jul 2025 428th LuisGoncalves05 🇵🇹 798 71 11ms 27 Jul 2025 428th CamegaZFC 798 71 11ms 30 Jul 2025 428th shelerr 798 71 10ms 22 Aug 2025 428th InigoK 🇺🇸 798 71 11ms 28 Aug 2025 428th janlelis 798 71 12ms 22 Sep 2025 428th rustykitty 🇺🇸 798 71 10ms 28 Oct 2025 428th Cube14yt 798 71 10ms 13 Nov 2025 428th guilhem-roy 🇫🇷 798 71 11ms 22 Nov 2025 428th CommandLeo 🇮🇹 798 71 10ms 27 Nov 2025 428th jkelly467 798 71 10ms 10 Dec 2025 428th Languag3 798 71 11ms 12 Dec 2025 428th Aquateraneal 🇺🇸 798 71 10ms 14 Feb 2026 468th inventshah 798 105 445ms 26 Mar 2025 468th Mukundan314 798 105 443ms 28 Apr 2025 470th ovs-code 🇩🇪 797 106 16ms 5 Jan 2025 471st DialFrost 🇸🇬 796 62 267ms 4 Jan 2025 471st bitsandbeyond 🇳🇱 796 62 331ms 3 Nov 2025 473rd CarsonChr 🇺🇸 795 104 10ms 5 Jan 2025 473rd m-tkach 🇺🇦 795 104 15ms 7 Jan 2025 473rd jared-hughes 795 104 11ms 7 Jan 2025 473rd Lv0Sys 🇵🇱 795 104 10ms 22 Feb 2026 477th DialFrost 🇸🇬 795 106 2ms 2 Jan 2025 477th NickTheEASDude 🇺🇸 795 106 3ms 8 Jan 2025 479th edsrzf 🇳🇿 795 126 4ms 26 Aug 2025 480th BREMAUCY 🇫🇷 794 38 3ms 9 Jan 2025 First Prev 401–480 of 1,051 Next Last