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 478th Lv0Sys 🇵🇱 795 104 10ms 22 Feb 2026 482nd DialFrost 🇸🇬 795 106 2ms 2 Jan 2025 482nd NickTheEASDude 🇺🇸 795 106 3ms 8 Jan 2025 484th edsrzf 🇳🇿 795 126 4ms 26 Aug 2025 485th BREMAUCY 🇫🇷 794 38 3ms 9 Jan 2025 486th snoozingnewt 🇨🇦 794 48 918ms 10 Dec 2025 486th error256 794 48 749ms 14 Feb 2026 488th JohandeRuiter 🇳🇱 794 83 4ms 21 Jan 2025 488th error256 794 83 4ms 25 Aug 2025 490th retrohun 794 118 197ms 26 Jan 2025 491st jared-hughes 794 185 18ms 6 Apr 2025 492nd j2e2 🇪🇸 789 107 15ms 7 Feb 2025 493rd GrayJoKing 🇦🇺 788 117 11ms 25 Feb 2026 494th adamnielson42 🇺🇸 787 72 11ms 26 Jan 2025 494th paulofreitas 787 72 10ms 10 May 2025 494th jacekwladzinski 787 72 10ms 2 Oct 2025 494th solisolu 787 72 10ms 2 Nov 2025 494th NoneTheFewer 787 72 11ms 27 Dec 2025 494th theunofficialcoder 787 72 10ms 27 Dec 2025 494th SectorCorruptor 787 72 11ms 3 Feb 2026 501st esmaycat 787 107 2ms 13 Jan 2025 502nd edsrzf 🇳🇿 787 110 7ms 8 Jan 2025 502nd dokutan 787 110 27ms 23 Feb 2025 504th edsrzf 🇳🇿 787 148 60ms 26 hours ago 505th sean-niemann 🇺🇸 786 107 446ms 29 Sep 2025 506th madex 🇩🇪 784 63 279ms 9 days ago 507th rucin93 🇵🇱 780 83 152ms 6 Jan 2025 508th voytxt 🇨🇿 780 106 11ms 4 Jan 2025 508th targrik 780 106 11ms 4 Apr 2025 510th Steffan153 🇫🇮 779 114 27ms 25 hours ago 511th MeWhenI 🇻🇦 777 92 393ms 6 Jan 2025 512th edsrzf 🇳🇿 777 100 117ms 25 Aug 2025 513th helbling 🇨🇭 776 73 10ms 4 Jan 2025 514th tailorspy 776 108 448ms 10 Jan 2025 515th MeWhenI 🇻🇦 776 129 5ms 6 Jan 2025 516th inventshah 775 85 2ms 26 Mar 2025 516th TeodorDyakov 🇧🇬 775 85 2ms 27 Sep 2025 518th IanUtley 775 109 16ms 6 Jan 2025 519th KatieLG 🇬🇧 774 39 3ms 7 Jan 2025 520th xsot 🇸🇬 774 91 5ms 23 Feb 2026 521st GolfingSuccess 🇬🇷 774 120 18ms 31 Jan 2026 522nd KasperKivimaeki 🇫🇮 773 22 1,021ms 15 Aug 2025 523rd Shanethegamer 🇺🇸 773 59 264ms 6 Jan 2025 524th charliegaming 773 107 11ms 24 Jan 2025 525th SirBogman 🇺🇸 772 108 1,418ms 23 Jan 2025 526th ejini6969 770 43 38ms 14 Jun 2025 527th AdrienHache 🇫🇷 769 93 427ms 6 Jan 2025 528th tatzyr 🇯🇵 769 191 15ms 6 Apr 2025 529th ovs-code 🇩🇪 768 66 433ms 3 Jan 2025 529th AlephSquirrel 768 66 463ms 5 Jan 2025 529th duckyluuk 🇳🇱 768 66 394ms 9 Jul 2025 529th TheZwierzLF 🇵🇱 768 66 465ms 24 Nov 2025 533rd error256 767 133 154ms 3 May 2025 533rd fantaize 767 133 158ms 15 days ago 535th kurkale6ka 766 74 12ms 15 Dec 2025 536th Mukundan314 766 86 2ms 28 Apr 2025 537th Shanethegamer 🇺🇸 766 94 112ms 6 Jan 2025 538th DialFrost 🇸🇬 765 92 5ms 14 days ago 539th Maznek 765 108 11ms 9 Jan 2025 540th namelessiw 765 110 405ms 3 Oct 2025 540th MeWhenI 🇻🇦 765 110 581ms 7 Nov 2025 542nd error256 764 66 1,312ms 7 Jan 2025 543rd sean-niemann 🇺🇸 762 85 150ms 21 Oct 2025 544th kg583 🇺🇸 761 153 81ms 41 hours ago 545th alemelis 760 60 291ms 15 Jul 2025 546th stefangimmillaro 759 45 17ms 6 Jan 2025 547th edsrzf 🇳🇿 758 95 99ms 1 Feb 2026 548th HumanoidCPU 758 109 11ms 7 Jan 2025 548th Andrey-Plotnikov 758 109 12ms 16 Jan 2025 548th acollett89 758 109 11ms 4 Aug 2025 548th snoozingnewt 🇨🇦 758 109 12ms 4 Nov 2025 548th olleicua 🇺🇸 758 109 10ms 9 Nov 2025 553rd edsrzf 🇳🇿 757 28 59ms 2 Nov 2025 554th FEZfan 🇦🇺 757 67 428ms 9 Jul 2025 554th m-tkach 🇺🇦 757 67 428ms 23 Jul 2025 556th DialFrost 🇸🇬 756 124 2,650ms 12 Jan 2025 557th Shanethegamer 🇺🇸 756 246 1,448ms 14 Apr 2025 558th andrewl64 755 75 11ms 25 Sep 2025 559th MostParsingVex 755 111 477ms 7 Jan 2025 560th snoozingnewt 🇨🇦 754 40 2ms 2 Nov 2025 First Prev 481–560 of 1,056 Next Last