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?
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 238th BREMAUCY 🇫🇷 849 39 36ms 6 Aug 2025 242nd ovs-code 🇩🇪 848 25 62ms 5 Jan 2025 243rd canissimia 🇦🇶 848 83 10ms 13 days ago 244th JayXon 🇺🇸 848 118 5ms 11 Jan 2025 245th edsrzf 🇳🇿 847 45 739ms 14 Feb 2026 245th albanian-laundromat 847 45 827ms 17 Feb 2026 245th CaedenHarper 🇨🇦 847 45 722ms 17 Feb 2026 248th error256 847 85 129ms 9 Jan 2025 248th edsrzf 🇳🇿 847 85 15ms 26 Dec 2025 250th HumanoidCPU 846 44 4ms 1 Feb 2025 250th plcc0 846 44 5ms 9 Apr 2025 252nd ovs-code 🇩🇪 846 106 16ms 5 Jan 2025 253rd antimon2 🇯🇵 845 54 267ms 6 Jan 2025 254th edsrzf 🇳🇿 845 110 17ms 9 Jul 2025 255th frankgraziano 845 111 2,342ms 13 Feb 2026 256th Yewzir 🇧🇪 844 60 386ms 2 Jan 2025 256th DialFrost 🇸🇬 844 60 425ms 5 Jan 2025 256th HumanoidCPU 844 60 404ms 7 Jan 2025 256th commandz0 🇺🇸 844 60 439ms 1 Sep 2025 256th snoozingnewt 🇨🇦 844 60 360ms 15 Oct 2025 261st GolfingSuccess 🇬🇷 844 93 25ms 23 days ago 262nd primo-ppcg 🇹🇭 843 117 42ms 27 Apr 2025 263rd edsrzf 🇳🇿 843 121 167ms 28 Jan 2026 264th JayXon 🇺🇸 842 99 1,307ms 10 Jan 2025 265th Shanethegamer 🇺🇸 842 100 2ms 5 Jan 2025 265th Waffle3z 842 100 2ms 7 Jan 2025 267th m-tkach 🇺🇦 840 105 31ms 9 Feb 2026 268th ovs-code 🇩🇪 839 60 1,370ms 5 Jan 2025 269th edsrzf 🇳🇿 839 130 307ms 25 Aug 2025 269th GolfingSuccess 🇬🇷 839 130 288ms 31 Jan 2026 271st Shanethegamer 🇺🇸 838 36 3ms 4 Jan 2025 272nd j2e2 🇪🇸 838 107 15ms 7 Feb 2025 273rd JayXon 🇺🇸 838 147 1,675ms 15 Sep 2025 274th JayXon 🇺🇸 837 93 119ms 8 Jan 2025 275th snyderek 🇺🇸 837 100 60ms 7 Jan 2025 276th DialFrost 🇸🇬 835 43 100ms 7 Jan 2025 276th SirBogman 🇺🇸 835 43 98ms 10 Jan 2025 276th nwellnhof 🇩🇪 835 43 97ms 14 Jan 2025 276th GrayJoKing 🇦🇺 835 43 106ms 17 Nov 2025 276th edsrzf 🇳🇿 835 43 105ms 10 Jan 2026 276th denkyuu1 835 43 89ms 23 Feb 2026 282nd MeWhenI 🇻🇦 835 77 58ms 6 Jan 2025 283rd vlpx 🇫🇮 835 99 11ms 6 Jan 2025 284th sean-niemann 🇺🇸 835 127 42ms 4 Jan 2025 285th ovs-code 🇩🇪 834 79 4ms 5 Jan 2025 286th GrayJoKing 🇦🇺 834 101 2ms 14 Jul 2025 287th m-tkach 🇺🇦 834 130 12ms 7 Jan 2025 288th MeWhenI 🇻🇦 833 41 19ms 5 Jan 2025 289th DialFrost 🇸🇬 833 55 74ms 1 Jan 2025 289th snoozingnewt 🇨🇦 833 55 74ms 11 Sep 2025 291st ovs-code 🇩🇪 833 68 11ms 5 Jan 2025 291st Bulmenisaurus 833 68 11ms 5 Jan 2025 291st zacjl 833 68 12ms 5 Jan 2025 291st HPWiz 🇳🇿 833 68 12ms 5 Jan 2025 291st AlephSquirrel 833 68 10ms 5 Jan 2025 291st fourth-bit 833 68 10ms 6 Jan 2025 291st lynn 833 68 10ms 6 Jan 2025 291st xnor-gate 833 68 12ms 8 Jan 2025 291st Powerroff 833 68 11ms 9 Jan 2025 291st esmaycat 833 68 12ms 13 Jan 2025 291st lambda-abstraction 833 68 10ms 15 Jan 2025 291st firegene 🇮🇪 833 68 10ms 15 Jan 2025 291st FieryIceStickie 833 68 11ms 17 Jan 2025 291st CLOStrophobic 🇮🇹 833 68 10ms 20 Jan 2025 291st bzijlema 🇳🇱 833 68 11ms 22 Jan 2025 291st prplz 🇦🇺 833 68 11ms 4 Feb 2025 291st error256 833 68 11ms 17 Apr 2025 291st 4atj 833 68 10ms 9 Jul 2025 291st GrayJoKing 🇦🇺 833 68 10ms 9 Jul 2025 291st Natanaelel 🇸🇪 833 68 32ms 17 Jul 2025 291st Andriamanitra 🇫🇮 833 68 11ms 17 Jul 2025 291st Kacarott 🇦🇺 833 68 11ms 18 Jul 2025 291st cros107 🇦🇺 833 68 10ms 9 Sep 2025 291st blaztoma 🇱🇹 833 68 11ms 30 Oct 2025 291st edsrzf 🇳🇿 833 68 10ms 30 Oct 2025 291st Emutis 🇱🇹 833 68 29ms 2 Nov 2025 291st sisyphus-ppcg 🇦🇺 833 68 10ms 24 Nov 2025 291st StefanHabel 🇨🇦 833 68 11ms 9 days ago 319th edsrzf 🇳🇿 831 111 11ms 26 days ago 320th frankgraziano 831 215 3,677ms 11 Aug 2025 First Prev 241–320 of 1,037 Next Last