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?
ROT13 in all languages in bytes. 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 Bytes Time Submitted 801st CaedenHarper 🇨🇦 576 116 4ms 21 Nov 2025 801st jgbaldwinbrown 576 116 5ms 2 Feb 2026 803rd te-chnical 572 114 18ms 7 May 2025 804th blaztoma 🇱🇹 571 117 4ms 21 Sep 2025 804th warmCabin 571 117 5ms 31 Dec 2025 806th ikskuh 570 147 70ms 26 Sep 2025 807th jbdrucker 570 153 16ms 24 Jan 2025 808th HumanoidCPU 570 182 134ms 21 Nov 2025 809th blaztoma 🇱🇹 570 186 37ms 21 Sep 2025 810th AstroOrbis 567 115 10ms 12 Jul 2025 810th Matter1024 🇮🇳 567 115 10ms 25 Aug 2025 812th yzhs 🇩🇪 562 116 10ms 17 Jan 2025 812th tomh1012 562 116 18ms 22 days ago 814th snoozingnewt 🇨🇦 561 83 212ms 27 Nov 2025 815th bac0id 561 119 2ms 10 Jan 2025 816th Jaydosu 557 117 11ms 16 Apr 2025 816th calebaitken 557 117 12ms 16 Apr 2025 816th adoxography 557 117 11ms 31 Aug 2025 819th janAkali 🇷🇺 556 152 407ms 18 Jan 2025 820th Shanethegamer 🇺🇸 555 160 26ms 5 Jan 2025 821st rucin93 🇵🇱 555 184 182ms 5 Jan 2025 822nd miabea73 553 152 479ms 26 Aug 2025 823rd JOrE20 553 182 26ms 27 days ago 824th Yewzir 🇧🇪 552 121 1ms 6 Jan 2025 825th snoozingnewt 🇨🇦 552 185 193ms 2 Nov 2025 826th michelebastione 🇮🇹 550 130 444ms 25 Dec 2025 827th jkelly467 547 98 2,489ms 10 Dec 2025 828th dokutan 545 155 4ms 11 Feb 2025 829th Natanaelel 🇸🇪 543 39 2ms 9 Jan 2025 830th SB-945 543 120 11ms 5 Jan 2025 830th randolchance 543 120 24ms 20 May 2025 830th yokasuretsu 543 120 13ms 12 Jul 2025 830th Bmrl7 543 120 18ms 23 Nov 2025 834th not-a-pokemon 543 123 4ms 18 Apr 2025 835th MeWhenI 🇻🇦 542 91 298ms 10 Jul 2025 836th dokutan 542 93 1,343ms 5 Feb 2025 837th CarsonChr 🇺🇸 542 132 422ms 5 Jan 2025 838th Siri-chan 542 161 12ms 8 Jan 2025 839th HumanoidCPU 541 189 198ms 1 Feb 2025 840th lukechampine 541 202 301ms 7 Jun 2025 841st ikskuh 539 124 1ms 27 Jun 2025 842nd ravnskjaer 🇩🇰 539 156 465ms 15 Dec 2025 843rd rbobillot 539 345 1,407ms 13 Jan 2025 844th JunkIce 538 121 11ms 12 Feb 2025 845th pquline 534 122 18ms 15 Mar 2025 846th shaneliu-zf 🇹🇼 531 101 2,621ms 30 May 2025 847th MeWhenI 🇻🇦 531 122 146ms 6 Jan 2025 848th snoozingnewt 🇨🇦 531 159 3ms 2 Nov 2025 849th frankgraziano 527 132 2ms 16 May 2025 850th Shanethegamer 🇺🇸 525 96 1,327ms 1 Jan 2025 851st vhoulbreque 🇫🇷 525 124 17ms 16 Feb 2025 852nd msbranicky 525 208 360ms 6 Jan 2025 853rd andrewl64 524 179 1,950ms 25 Sep 2025 854th cyrilboyer 🇫🇷 524 195 156ms 13 Jan 2025 855th Mikey-Beep 🇬🇧 521 125 11ms 8 Jul 2025 856th DialFrost 🇸🇬 520 97 1,301ms 5 Jan 2025 857th Schmitt-Very-Cool 519 162 527ms 3 Oct 2025 858th madex 🇩🇪 519 197 195ms 4 Jan 2025 859th iilegacyyii 518 129 2ms 16 Jan 2025 860th olleicua 🇺🇸 517 64 39ms 9 Mar 2025 861st DialFrost 🇸🇬 517 87 7ms 11 Jan 2025 862nd osNiko 🇧🇷 517 126 12ms 16 Aug 2025 863rd MyXoToD 🇩🇪 516 169 11ms 20 May 2025 864th CaedenHarper 🇨🇦 515 139 415ms 16 Oct 2025 865th SuperFola 515 228 50ms 2 hours ago 866th JDiLenarda 🇫🇷 514 162 1,380ms 30 Jan 2026 867th blaztoma 🇱🇹 514 196 27ms 21 Sep 2025 868th Bobini1 🇵🇱 513 127 17ms 15 Jan 2025 868th matsagad 513 127 35ms 16 Jan 2025 870th Mabeloid 🇳🇴 510 131 4ms 21 Oct 2025 871st Siri-chan 508 201 178ms 8 Jan 2025 872nd tjwrenn 505 129 11ms 27 Jan 2025 873rd duckyluuk 🇳🇱 505 191 6ms 29 Jan 2026 874th frankgraziano 505 210 40ms 16 May 2025 875th msbranicky 504 138 2ms 4 Jan 2025 876th alaaeelsayed 504 167 428ms 15 Jan 2025 877th madeforlosers 504 173 10ms 14 Jan 2025 878th balloffur 502 167 451ms 7 Dec 2025 879th Shanethegamer 🇺🇸 500 141 54ms 2 Jan 2025 880th Kacarott 🇦🇺 500 193 7ms 26 Apr 2025 First Prev 801–880 of 1,074 Next Last