The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 29 hours. Why not try and solve them ahead of time?
Lucky Numbers 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 720th TheZwierzLF 🇵🇱 558 80 1,933ms 25 Dec 2025 722nd HumanoidCPU 558 119 139ms 7 Nov 2024 723rd madex 🇩🇪 558 122 3ms 29 Mar 2022 724th kkoenig 558 201 292ms 7 Sep 2025 725th h3ra993huskp 🇯🇵 557 163 587ms 30 Nov 2025 726th SirFireball3521 556 79 764ms 15 Mar 2023 727th commandz0 🇺🇸 556 91 102ms 21 Sep 2022 727th MaxElf999 556 91 3,503ms 28 Sep 2022 727th fkantelberg 556 91 53ms 7 Aug 2023 727th sultan 556 91 30ms 5 Mar 2024 731st HumanoidCPU 555 202 284ms 26 Aug 2024 732nd msbranicky 554 87 513ms 17 Jan 2024 733rd albanian-laundromat 554 260 2,813ms 23 Oct 2025 734th varhammer 553 153 210ms 13 Dec 2023 735th CatsAreFluffy 553 157 79ms 10 Jan 2023 736th Ailko 🇧🇪 550 92 11ms 6 May 2022 736th ComputerKWasTaken 🇺🇸 550 92 11ms 23 Oct 2024 738th TheLazySquid 550 104 190ms 26 Sep 2024 739th commandz0 🇺🇸 548 88 605ms 1 Sep 2025 740th kmathis22 547 166 463ms 23 Dec 2025 741st emgordon154 547 205 306ms 18 Jan 2025 742nd edsrzf 🇳🇿 546 129 12ms 11 Nov 2025 743rd Lv0Sys 🇵🇱 544 82 99ms 27 Feb 2026 744th TobyBoyne 🇬🇧 544 93 3,365ms 3 Mar 2022 744th P-Quentin 🇫🇷 544 93 26ms 10 Aug 2022 744th jtaxen 544 93 101ms 26 Mar 2024 744th jameswmccarty 544 93 10ms 10 Jul 2024 744th codingisgreatbutiamnot 544 93 721ms 6 Aug 2025 744th Googolplexo 🇷🇺 544 93 192ms 2 days ago 750th rifatx 544 147 503ms 16 Jul 2024 751st 0xjac 🇨🇭 542 207 308ms 7 Jun 2025 752nd albanian-laundromat 541 125 134ms 20 Aug 2025 753rd MeWhenI 🇻🇦 540 101 2,081ms 15 Sep 2025 754th hamhub7 540 148 465ms 8 Aug 2022 755th Re-Adventures 🇮🇳 539 106 27ms 1 Feb 2023 756th jacobly0 🇺🇸 539 208 281ms 17 Aug 2023 757th denkyuu1 538 83 2,745ms 2 days ago 758th adamnielson42 🇺🇸 538 94 60ms 21 Aug 2023 758th brochmann 🇸🇪 538 94 12ms 28 Oct 2023 758th 40fied4t 538 94 37ms 1 Jun 2025 761st Shanethegamer 🇺🇸 538 167 146ms 27 Sep 2024 762nd DialFrost 🇸🇬 536 71 58ms 31 Oct 2023 763rd Yewzir 🇧🇪 535 278 1,874ms 15 Nov 2025 764th MeWhenI 🇻🇦 534 92 449ms 15 Feb 2023 765th rifatx 534 210 300ms 17 Jul 2024 766th retrohun 533 100 592ms 1 Mar 2022 767th m42km 532 95 49ms 16 Dec 2023 767th Natanaelel 🇸🇪 532 95 29ms 15 Jul 2025 769th snyderek 🇺🇸 532 163 77ms 17 Oct 2024 770th Protothor 529 108 12ms 21 Jun 2025 771st edsrzf 🇳🇿 529 212 287ms 8 Nov 2024 772nd j-Ewan 527 96 104ms 4 Mar 2022 772nd nullie 527 96 82ms 9 Jun 2022 772nd andrewjc2000 527 96 29ms 28 Jul 2025 772nd Bmrl7 527 96 130ms 24 Dec 2025 776th annaproxy 526 152 408ms 28 Mar 2022 777th JGDoerrer 526 173 167ms 5 Apr 2022 778th janbehrens 🇩🇪 522 153 385ms 3 Mar 2022 779th GolfinK 521 53 35ms 22 Nov 2024 780th IsaacAlexBarden 521 97 28ms 13 Feb 2025 781st JRaspass 🇬🇧 521 215 287ms 7 Feb 2024 782nd XenThe 🇬🇧 520 110 13ms 6 Jul 2025 783rd ibexq 520 131 11ms 2 May 2023 784th MeWhenI 🇻🇦 519 147 1,314ms 10 Mar 2022 785th kmathis22 519 216 276ms 10 Oct 2025 786th sleepyStick 516 98 10ms 11 Mar 2022 786th damoose717 516 98 11ms 24 May 2025 788th janbehrens 🇩🇪 515 157 478ms 24 Mar 2022 789th Andrey135296 511 99 198ms 29 Nov 2024 790th madex 🇩🇪 511 144 3,122ms 15 days ago 791st Yewzir 🇧🇪 510 220 303ms 3 Jan 2024 792nd MeWhenI 🇻🇦 509 131 26ms 6 Aug 2023 793rd CatsAreFluffy 508 134 15ms 27 Jan 2023 794th emgordon154 507 100 300ms 6 Sep 2024 795th Fishron 506 100 91ms 18 Jun 2022 795th vishwathg 506 100 112ms 5 Oct 2023 795th 4ndyJ 🇬🇧 506 100 220ms 23 Dec 2023 795th chartung17 506 100 114ms 1 Jan 2024 799th MathisBullinger 506 113 47ms 27 Mar 2022 800th adriweb 🇫🇷 506 137 39ms 26 Sep 2023 First Prev 721–800 of 1,576 Next Last