The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 4 days. Why not try and solve them ahead of time?
Set 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 241st kg583 🇺🇸 783 178 428ms 29 Oct 2025 242nd MeWhenI 🇻🇦 782 828 2,855ms 18 Nov 2025 243rd pardouin 🇫🇷 781 158 512ms 3 Apr 2025 244th SirBogman 🇺🇸 780 71 693ms 11 Jul 2025 245th FEZfan 🇦🇺 777 124 566ms 26 Apr 2025 246th FEZfan 🇦🇺 774 165 444ms 15 Feb 2026 247th emgordon154 774 201 222ms 4 Jun 2025 248th stefangimmillaro 773 208 654ms 6 Oct 2025 249th moustave 772 145 32ms 16 Apr 2025 249th za3k 772 145 33ms 17 Apr 2025 251st canissimia 🇦🇶 772 374 67ms 11 Apr 2025 252nd snoozingnewt 🇨🇦 771 125 481ms 20 Nov 2025 253rd kg583 🇺🇸 771 141 46ms 19 Jan 2026 254th nwellnhof 🇩🇪 770 136 220ms 3 Feb 2026 255th edsrzf 🇳🇿 769 209 653ms 24 Sep 2025 256th 2bular 767 43 171ms 1 Apr 2025 257th keelimeguy 🇺🇸 767 146 42ms 7 May 2025 257th FlorianCassayre 🇫🇷 767 146 27ms 5 Aug 2025 257th Bmrl7 767 146 24ms 25 Dec 2025 257th nemoyatpeace 767 146 26ms 19 Jan 2026 261st DialFrost 🇸🇬 764 126 514ms 18 Feb 2025 262nd error256 764 166 125ms 22 Jan 2026 263rd acotis 762 204 288ms 3 Jun 2025 264th edsrzf 🇳🇿 761 100 1,301ms 2 Jun 2025 265th edsrzf 🇳🇿 761 131 31ms 21 Apr 2025 266th saito-ta 🇯🇵 759 167 2ms 31 Mar 2025 267th MeWhenI 🇻🇦 758 127 549ms 25 Jun 2025 268th error256 758 237 302ms 22 Jan 2026 269th Yax42 🇫🇷 752 153 439ms 20 Jan 2026 270th keelimeguy 🇺🇸 751 239 299ms 27 Apr 2025 271st SirBogman 🇺🇸 750 44 74ms 26 Mar 2025 272nd sean-niemann 🇺🇸 749 170 142ms 21 Apr 2025 273rd Lv0Sys 🇵🇱 748 240 285ms 22 Feb 2026 274th error256 743 207 70ms 25 Apr 2025 275th Andriamanitra 🇫🇮 742 151 30ms 29 Mar 2025 275th rucin93 🇵🇱 742 151 26ms 15 Apr 2025 277th klixel 🇨🇦 737 152 347ms 5 Apr 2025 278th Shanethegamer 🇺🇸 736 157 74ms 27 Mar 2025 279th edsrzf 🇳🇿 735 133 41ms 11 Apr 2025 280th Yax42 🇫🇷 733 136 14ms 20 Jan 2026 281st ovs-code 🇩🇪 733 173 2ms 31 Mar 2025 282nd stefangimmillaro 733 212 236ms 4 Jun 2025 283rd dokutan 732 153 25ms 28 Mar 2025 284th error256 731 182 258ms 27 Apr 2025 285th SirBogman 🇺🇸 730 92 53ms 19 Jul 2025 285th TheZwierzLF 🇵🇱 730 92 53ms 5 Jan 2026 287th Shanethegamer 🇺🇸 727 155 719ms 29 Mar 2025 288th DialFrost 🇸🇬 725 114 1,105ms 23 Jun 2025 289th pardouin 🇫🇷 725 175 149ms 4 Apr 2025 290th ovs-code 🇩🇪 725 193 77ms 30 Mar 2025 291st mousetail 🇳🇱 721 106 1,469ms 1 Apr 2025 292nd Mukundan314 720 176 9ms 24 Nov 2025 293rd edsrzf 🇳🇿 720 216 214ms 2 Apr 2025 294th Kacarott 🇦🇺 719 126 627ms 6 Apr 2025 295th JunkIce 719 134 412ms 9 Jul 2025 296th Mukundan314 718 195 69ms 28 Apr 2025 296th snyderek 🇺🇸 718 195 64ms 3 May 2025 298th Lv0Sys 🇵🇱 717 139 16ms 22 Feb 2026 299th CaedenHarper 🇨🇦 716 251 278ms 10 Nov 2025 300th emgordon154 715 142 2,757ms 31 May 2025 301st Shanethegamer 🇺🇸 715 152 46ms 6 Apr 2025 302nd FortuiteMan 🇫🇷 713 157 19ms 20 Jun 2025 302nd yujqiao 713 157 30ms 16 Dec 2025 304th xsot 🇸🇬 708 119 85ms 13 Apr 2025 305th CaedenHarper 🇨🇦 708 136 508ms 4 Apr 2025 306th olleicua 🇺🇸 707 95 53ms 22 Apr 2025 307th tailorspy 707 198 66ms 5 May 2025 308th stefangimmillaro 707 254 290ms 9 May 2025 309th albanian-laundromat 705 524 13ms 11 Dec 2025 310th calebaitken 704 159 25ms 10 Apr 2025 311th edsrzf 🇳🇿 704 160 577ms 27 Apr 2025 312th edsrzf 🇳🇿 701 145 2,807ms 21 Apr 2025 313th emgordon154 700 96 60ms 27 Mar 2025 314th jameswmccarty 700 160 18ms 27 Mar 2025 315th ovs-code 🇩🇪 700 172 187ms 4 Apr 2025 316th Shanethegamer 🇺🇸 698 109 1,313ms 27 Mar 2025 317th duckyluuk 🇳🇱 698 137 283ms 15 Apr 2025 318th ovs-code 🇩🇪 697 130 666ms 6 Apr 2025 319th error256 697 177 563ms 24 Apr 2025 320th Andriamanitra 🇫🇮 697 180 155ms 29 Mar 2025 First Prev 241–320 of 491 Next Last