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?
ln 2 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 560th Pyroan 712 71 18ms 11 Mar 2025 562nd lynn 707 223 208ms 4 Aug 2023 563rd XioR112 🇵🇱 702 72 17ms 29 Aug 2023 563rd rollershutter 702 72 18ms 9 Nov 2023 563rd Dataen 702 72 18ms 10 Jan 2024 563rd Hebelub 702 72 17ms 10 Jan 2024 563rd jfallon1997 702 72 17ms 30 Apr 2024 563rd pinguicula 702 72 10ms 15 Aug 2024 563rd ImpressedByRocks 702 72 178ms 24 May 2025 563rd FortuiteMan 🇫🇷 702 72 18ms 28 Sep 2025 563rd aksyristos 702 72 19ms 35 mins ago 572nd msbranicky 699 55 220ms 12 Jan 2024 573rd tomh1012 699 127 477ms 16 Sep 2025 574th MeWhenI 🇻🇦 695 87 1,606ms 9 May 2024 574th kg583 🇺🇸 695 87 82ms 23 Nov 2025 576th MeWhenI 🇻🇦 695 171 2,186ms 28 Mar 2025 577th msbranicky 693 199 799ms 31 Aug 2023 578th zakariamouhid 692 73 2,783ms 1 Aug 2023 578th adamnielson42 🇺🇸 692 73 18ms 14 Aug 2023 578th jtaxen 692 73 17ms 17 Mar 2024 578th ei14 692 73 179ms 23 May 2024 578th EnTerr 692 73 17ms 17 Jun 2024 578th YAJUE114514 692 73 10ms 10 Dec 2025 584th stefangimmillaro 691 190 133ms 4 Jun 2025 585th Daniikk1012 690 41 268ms 3 Nov 2025 586th BREMAUCY 🇫🇷 689 53 44ms 26 Dec 2025 587th dokutan 685 284 2ms 7 Nov 2025 588th DialFrost 🇸🇬 681 55 9ms 22 Feb 2026 589th albanian-laundromat 675 176 2,360ms 18 Oct 2025 590th clemmers 🇺🇸 674 75 18ms 1 Aug 2023 590th bac0id 674 75 18ms 20 Sep 2023 592nd iczelia 🇩🇪 673 75 21ms 16 Oct 2025 593rd msbranicky 665 76 17ms 3 Aug 2023 593rd StHagel 665 76 18ms 3 Aug 2023 593rd SniperSmiley 🇺🇸 665 76 17ms 15 Aug 2023 593rd RYNO8 665 76 17ms 20 Aug 2023 593rd epic-programmer-guy 665 76 18ms 31 Dec 2023 593rd Just4FunCoder 665 76 17ms 26 Feb 2024 593rd sultan 665 76 17ms 9 Mar 2024 593rd stertooy 🇧🇪 665 76 18ms 11 Jun 2024 593rd xyangst 665 76 18ms 12 Oct 2024 593rd OSYCh314 🇦🇺 665 76 18ms 2 Nov 2024 593rd Unknownuserfrommars 665 76 18ms 20 Nov 2024 593rd austinleblanc 665 76 18ms 1 Mar 2025 593rd 0dyse 665 76 19ms 29 Apr 2025 593rd codewrite 🇬🇧 665 76 18ms 25 May 2025 593rd GoldStar184 665 76 18ms 17 Jul 2025 593rd muser-logiccpu 🇺🇦 665 76 18ms 9 Aug 2025 593rd cthierfelder 🇲🇨 665 76 18ms 8 Sep 2025 593rd LostSyntax21 🇬🇧 665 76 17ms 9 Nov 2025 593rd Andrey2001 665 76 19ms 15 Dec 2025 593rd Aquateraneal 🇺🇸 665 76 18ms 19 Feb 2026 613th tatzyr 🇯🇵 664 55 41ms 6 Feb 2025 614th tomh1012 664 76 20ms 16 days ago 615th rollershutter 662 58 202ms 8 Nov 2023 616th MeWhenI 🇻🇦 661 183 148ms 1 Aug 2023 617th CaedenHarper 🇨🇦 657 65 2,375ms 27 Sep 2025 618th willdaspit 656 77 20ms 4 Aug 2023 618th jgh713 656 77 17ms 29 Aug 2023 618th diquah 656 77 18ms 1 Nov 2023 618th cooljoseph1 656 77 18ms 24 Dec 2023 618th jameswmccarty 656 77 17ms 4 Jun 2024 618th swtchblade 656 77 19ms 15 Jul 2025 618th Voltrifrodec 🇸🇰 656 77 19ms 7 Nov 2025 625th m-tkach 🇺🇦 656 254 73ms 17 Dec 2023 626th ovs-code 🇩🇪 654 211 1,735ms 14 Sep 2025 627th 4hg 🇺🇸 651 69 819ms 17 Sep 2023 628th edsrzf 🇳🇿 649 183 2,225ms 18 Jan 2025 629th Coolbeansyeah 648 78 18ms 13 May 2024 629th codingisgreatbutiamnot 648 78 18ms 29 Jul 2024 629th piano-miles 648 78 18ms 4 May 2025 629th Zhenyu-Bo 648 78 19ms 31 Jul 2025 629th jacekwladzinski 648 78 21ms 4 Oct 2025 634th Lydxn 🇨🇦 647 176 497ms 6 Aug 2023 635th mousetail 🇳🇱 644 60 1,017ms 24 Oct 2024 636th rifatx 644 138 476ms 15 Jul 2024 637th jared-hughes 643 177 533ms 24 Sep 2025 638th heanyang1 640 60 213ms 29 May 2025 639th eiburns 640 79 18ms 15 Sep 2023 639th Mabeloid 🇳🇴 640 79 18ms 7 Sep 2024 First Prev 561–640 of 1,822 Next Last