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 561st error256 743 113 489ms 24 Sep 2025 562nd kkoenig 742 147 297ms 7 Sep 2025 563rd stefangimmillaro 741 105 113ms 3 Jan 2025 564th qwertyuiop3 🇷🇺 741 113 464ms 15 May 2025 565th anter69 🇭🇺 740 68 1,293ms 13 Mar 2025 566th rucin93 🇵🇱 740 89 2ms 2 Jan 2025 566th Alex-x90 🇺🇸 740 89 4ms 4 Jan 2025 568th zakariamouhid 738 112 11ms 8 Jan 2025 568th gnlow 🇰🇷 738 112 11ms 11 Feb 2025 570th snoozingnewt 🇨🇦 738 124 104ms 20 Nov 2025 571st emgordon154 738 252 1,439ms 15 Apr 2025 572nd Just4FunCoder 736 77 11ms 24 Sep 2025 573rd MeWhenI 🇻🇦 734 69 480ms 3 Jan 2025 573rd roguh 🇬🇹 734 69 366ms 18 Jul 2025 575th SirBogman 🇺🇸 733 49 33ms 9 Jan 2025 576th CaedenHarper 🇨🇦 732 113 9ms 31 Aug 2025 577th emgordon154 731 29 133ms 11 Sep 2025 578th rucin93 🇵🇱 731 88 112ms 18 Feb 2025 579th SirBogman 🇺🇸 728 115 65ms 16 Jan 2025 580th duckyluuk 🇳🇱 727 108 41ms 4 Jan 2025 581st ehulinsky 🇺🇸 726 78 11ms 29 Mar 2025 582nd Yax42 🇫🇷 725 114 10ms 13 Nov 2025 583rd qwertyuiop3 🇷🇺 724 91 1ms 15 May 2025 584th CLOStrophobic 🇮🇹 719 144 136ms 28 May 2025 584th Andriamanitra 🇫🇮 719 144 149ms 7 Jun 2025 586th yhm138 717 79 10ms 16 Feb 2025 587th MostParsingVex 716 92 4ms 7 Jan 2025 587th Lv0Sys 🇵🇱 716 92 4ms 10 Dec 2025 589th j2e2 🇪🇸 716 103 4ms 6 Feb 2025 590th MarcMush 🇫🇷 713 64 311ms 29 Jan 2025 591st smclaughlin-cf 713 116 10ms 21 Feb 2025 592nd luuumine 🇫🇷 713 143 146ms 8 Dec 2025 593rd MeWhenI 🇻🇦 713 153 285ms 7 Jan 2025 594th edsrzf 🇳🇿 711 124 27ms 2 Feb 2026 595th albanian-laundromat 710 141 4ms 5 Jul 2025 596th FlorianCassayre 🇫🇷 708 80 11ms 14 Jan 2025 597th muser-logiccpu 🇺🇦 708 119 2ms 24 Jul 2025 598th CaedenHarper 🇨🇦 708 154 280ms 13 days ago 599th Kacarott 🇦🇺 707 91 68ms 6 Jan 2025 600th Cube14yt 707 117 10ms 13 Nov 2025 601st DialFrost 🇸🇬 706 253 3,967ms 13 Aug 2025 602nd stackofbears 704 51 34ms 10 Jan 2025 603rd emgordon154 704 145 172ms 14 Mar 2025 604th DialFrost 🇸🇬 701 94 4ms 3 Jan 2025 605th DialFrost 🇸🇬 700 92 104ms 30 Nov 2025 606th tobeannouncd 700 148 129ms 20 Jan 2025 607th CLOStrophobic 🇮🇹 700 158 41ms 13 Feb 2025 608th stefangimmillaro 699 131 159ms 3 Jan 2025 609th imperfect-fourth 699 156 278ms 11 days ago 610th stefangimmillaro 698 121 380ms 6 Jan 2025 611th pardouin 🇫🇷 697 78 2,728ms 4 Jan 2025 611th stefangimmillaro 697 78 2,628ms 4 Jan 2025 611th ScottHamper 697 78 2,580ms 19 Jan 2025 614th fuzzylojik-golf 🇺🇸 694 103 374ms 23 May 2025 615th j2e2 🇪🇸 693 95 1ms 19 Feb 2025 615th iczelia 🇩🇪 693 95 4ms 24 Sep 2025 617th GolfingSuccess 🇬🇷 693 108 4ms 31 Dec 2024 617th Shanethegamer 🇺🇸 693 108 4ms 1 Jan 2025 617th helbling 🇨🇭 693 108 4ms 4 Jan 2025 617th dokutan 693 108 4ms 6 Jan 2025 617th galloj 🇨🇿 693 108 4ms 23 Jan 2025 617th edsrzf 🇳🇿 693 108 4ms 14 Mar 2025 617th stefangimmillaro 693 108 4ms 12 Jul 2025 617th iczelia 🇩🇪 693 108 4ms 21 Sep 2025 617th emgordon154 693 108 4ms 3 Nov 2025 626th albanian-laundromat 693 153 48ms 8 Sep 2025 627th snoozingnewt 🇨🇦 692 93 110ms 26 Dec 2025 628th DialFrost 🇸🇬 691 66 343ms 3 Jan 2025 629th frankgraziano 691 82 11ms 9 Jul 2025 630th SirBogman 🇺🇸 690 143 144ms 3 Jun 2025 631st elgan65536 🇺🇸 689 148 161ms 16 Jan 2025 632nd MeWhenI 🇻🇦 686 122 433ms 6 Jan 2025 633rd iczelia 🇩🇪 686 151 133ms 21 Sep 2025 634th stefangimmillaro 685 144 46ms 14 Jan 2025 635th didion0 🇺🇸 683 121 12ms 24 Feb 2025 635th SebassNoob 683 121 11ms 8 Aug 2025 637th nullie 680 150 141ms 6 Apr 2025 638th qbitYouri 679 124 2ms 4 Apr 2025 639th snoozingnewt 🇨🇦 678 53 97ms 2 Nov 2025 640th iliazeus 678 122 13ms 25 Nov 2025 First Prev 561–640 of 1,037 Next Last