The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 24 hours. Why not try and solve them ahead of time?
Number Spiral 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 400th Lv0Sys 🇵🇱 687 118 9ms 27 Feb 2026 402nd SirBogman 🇺🇸 686 78 39ms 19 May 2022 403rd annaproxy 686 144 117ms 15 Apr 2022 404th edsrzf 🇳🇿 685 44 3ms 14 hours ago 405th Shanethegamer 🇺🇸 684 92 10ms 27 Jan 2022 405th ovs-code 🇩🇪 684 92 9ms 11 Mar 2024 407th Yewzir 🇧🇪 684 170 396ms 2 Oct 2025 407th stefangimmillaro 684 170 505ms 6 Oct 2025 409th MeWhenI 🇻🇦 683 121 6ms 9 May 2024 409th emgordon154 683 121 8ms 6 Dec 2024 411th CLOStrophobic 🇮🇹 683 145 5ms 1 Mar 2025 412th JRaspass 🇬🇧 682 104 3ms 10 Jun 2022 412th nephila-nacrea 🇬🇧 682 104 3ms 10 Jun 2022 414th dokutan 682 139 145ms 28 Mar 2024 415th DialFrost 🇸🇬 680 130 4ms 17 Nov 2023 416th AlephSquirrel 680 135 4ms 22 Apr 2023 417th HumanoidCPU 679 359 10ms 21 May 2024 418th GrayJoKing 🇦🇺 678 101 72ms 9 Dec 2023 419th MeWhenI 🇻🇦 677 79 31ms 16 Aug 2022 420th Yewzir 🇧🇪 677 122 6ms 18 Dec 2023 421st MeWhenI 🇻🇦 677 175 3ms 24 Jul 2023 422nd lynn 676 93 9ms 27 Jan 2022 422nd prplz 🇦🇺 676 93 9ms 25 May 2022 422nd Seek64 🇩🇪 676 93 10ms 30 Sep 2023 422nd blaztoma 🇱🇹 676 93 9ms 26 days ago 426th Shanethegamer 🇺🇸 674 116 85ms 15 Jan 2023 427th stefangimmillaro 674 151 446ms 11 Nov 2024 428th ovs-code 🇩🇪 673 90 470ms 11 Mar 2024 429th MeWhenI 🇻🇦 670 192 274ms 9 Feb 2023 430th DialFrost 🇸🇬 669 94 10ms 2 Oct 2023 430th davecame 669 94 9ms 30 Sep 2024 432nd AlephSquirrel 669 148 5ms 17 Mar 2023 433rd Natanaelel 🇸🇪 668 148 127ms 16 Jun 2025 434th Yewzir 🇧🇪 668 160 133ms 4 Feb 2024 435th dokutan 665 367 10ms 31 Oct 2023 435th CaedenHarper 🇨🇦 665 367 10ms 24 Jan 2025 437th PixelSoftwareStudios 🇺🇸 662 95 11ms 11 Jun 2024 437th edsrzf 🇳🇿 662 95 42ms 2 hours ago 439th DialFrost 🇸🇬 660 169 124ms 25 Dec 2023 440th dokutan 660 195 301ms 1 Apr 2024 441st Yewzir 🇧🇪 659 115 1,070ms 15 Nov 2025 442nd tayloia 🇬🇧 659 123 9ms 2 May 2023 442nd targrik 659 123 9ms 9 Jun 2025 444th yzhs 🇩🇪 659 150 114ms 26 Jun 2023 445th Alessandro-Balconi 🇮🇹 658 90 89ms 15 Jul 2023 445th DialFrost 🇸🇬 658 90 87ms 18 Mar 2025 447th jared-hughes 658 128 2ms 17 Jul 2022 448th emgordon154 658 169 76ms 8 Feb 2026 449th plcc0 657 119 80ms 11 hours ago 450th Jasper-Ty 🇵🇭 657 136 1ms 27 Apr 2024 451st dokutan 657 167 2ms 13 Apr 2024 452nd HumanoidCPU 657 182 3ms 20 Nov 2025 453rd emgordon154 657 196 297ms 17 Jan 2025 454th dokutan 656 165 1ms 1 Apr 2024 455th stefangimmillaro 655 169 102ms 31 Aug 2023 456th Yewzir 🇧🇪 654 145 151ms 22 Dec 2024 457th DialFrost 🇸🇬 653 150 2ms 15 Apr 2025 458th sean-niemann 🇺🇸 652 112 2ms 19 Nov 2023 459th stefangimmillaro 651 169 133ms 13 Nov 2023 460th pschmid0 🇺🇸 650 136 4ms 23 Oct 2022 461st BlankSpruce 650 171 59ms 9 Jan 2026 462nd namelessiw 648 97 10ms 10 Apr 2024 463rd error256 648 138 2ms 24 Dec 2024 464th blaztoma 🇱🇹 647 205 42ms 27 Dec 2025 465th Yewzir 🇧🇪 646 113 1ms 21 Dec 2023 466th snoozingnewt 🇨🇦 646 137 5ms 16 Sep 2025 467th nwellnhof 🇩🇪 645 83 33ms 5 Oct 2022 467th tatzyr 🇯🇵 645 83 38ms 15 Feb 2025 469th duckyluuk 🇳🇱 644 186 9ms 18 Dec 2024 470th madex 🇩🇪 643 139 1ms 18 Mar 2022 471st m-tkach 🇺🇦 640 153 2ms 27 Oct 2022 472nd HumanoidCPU 639 174 74ms 29 Aug 2024 473rd stefangimmillaro 638 127 9ms 27 Sep 2024 474th hemphen 636 160 412ms 6 Aug 2022 475th emgordon154 636 234 4ms 21 Oct 2025 476th Flekay 🇩🇪 635 99 9ms 15 Feb 2026 477th MeWhenI 🇻🇦 630 179 448ms 4 Mar 2022 478th ryyyn 🇺🇸 629 100 10ms 15 Dec 2025 479th MeWhenI 🇻🇦 629 185 495ms 7 Nov 2025 480th KenanSi 628 48 2ms 24 Feb 2022 First Prev 401–480 of 1,804 Next Last