The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 3 days. Why not try and solve them ahead of time?
Sierpiński Triangle 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 641st emgordon154 674 66 35ms 19 Nov 2025 642nd XenThe 🇬🇧 674 68 10ms 14 Jun 2025 643rd 09cf 673 80 2ms 1 Dec 2025 644th annaproxy 673 88 64ms 11 Dec 2022 645th snoozingnewt 🇨🇦 673 92 80ms 23 Oct 2025 646th yzhs 🇩🇪 673 99 113ms 18 Jan 2020 647th cure-honey 🇯🇵 672 63 266ms 15 Jul 2021 648th Shanethegamer 🇺🇸 672 93 4ms 19 Oct 2024 648th edsrzf 🇳🇿 672 93 4ms 13 Feb 2026 650th MeWhenI 🇻🇦 671 78 1ms 12 Nov 2022 651st SmartK8 🇨🇿 671 93 395ms 29 Oct 2022 652nd argusdusty 🇺🇸 670 79 10ms 31 Dec 2020 652nd scpchicken 🇵🇼 670 79 11ms 13 Mar 2022 652nd mathb0y512 670 79 10ms 24 Nov 2022 652nd Bulmenisaurus 670 79 10ms 5 Jan 2025 652nd InigoK 🇺🇸 670 79 10ms 22 Sep 2025 652nd Emutis 🇱🇹 670 79 10ms 18 Dec 2025 658th snoozingnewt 🇨🇦 669 97 96ms 20 Nov 2025 659th bluebear94 668 53 106ms 12 Feb 2018 660th Shanethegamer 🇺🇸 668 66 1,301ms 2 Jul 2021 661st BREMAUCY 🇫🇷 668 73 413ms 1 Nov 2025 662nd jared-hughes 667 45 35ms 25 Sep 2021 663rd kmathis22 667 104 467ms 7 Dec 2025 664th steffan-polygolf 665 49 40ms 21 Feb 2024 665th didion0 🇺🇸 665 69 9ms 9 Feb 2021 666th Jasper-Ty 🇵🇭 665 81 1ms 23 Apr 2022 666th jupj 🇫🇮 665 81 2ms 8 Oct 2022 668th Shanethegamer 🇺🇸 665 93 88ms 13 Dec 2022 669th steffan-polygolf 663 95 2ms 14 Feb 2024 669th FlyingPenguin223 663 95 2ms 10 Mar 2025 671st MeWhenI 🇻🇦 662 64 243ms 15 Feb 2023 672nd redbeancola 662 80 11ms 11 Oct 2021 672nd QuincyNash 🇺🇸 662 80 11ms 29 Nov 2022 672nd aksyristos 662 80 10ms 28 Feb 2023 672nd 2011-Chan-Ethan 662 80 17ms 9 Jul 2023 672nd FlorianCassayre 🇫🇷 662 80 10ms 18 Sep 2023 677th madeforlosers 661 100 39ms 7 May 2024 678th kritixilithos 660 74 1ms 27 May 2024 679th boxjelly 660 101 114ms 6 Jan 2021 679th the-zammers 660 101 132ms 15 Dec 2023 679th Awsute 660 101 119ms 20 Aug 2024 682nd Yewzir 🇧🇪 660 151 1,864ms 8 May 2024 683rd SirBogman 🇺🇸 659 74 488ms 16 Jan 2024 683rd dokutan 659 74 382ms 14 Feb 2026 685th stefangimmillaro 659 87 2,509ms 15 Nov 2024 686th yzhs 🇩🇪 658 67 1,280ms 3 Aug 2021 687th DialFrost 🇸🇬 658 94 90ms 27 May 2024 688th Secozzi 657 82 2ms 14 Mar 2021 688th madex 🇩🇪 657 82 2ms 2 Aug 2021 690th DialFrost 🇸🇬 657 147 288ms 29 Nov 2023 690th Yewzir 🇧🇪 657 147 281ms 3 Jan 2024 692nd elgan65536 🇺🇸 656 114 127ms 7 Feb 2026 693rd SirBogman 🇺🇸 655 54 122ms 23 Jan 2024 694th TheZwierzLF 🇵🇱 655 68 36ms 21 Dec 2025 695th weliveinhell 🇭🇹 655 70 11ms 30 Sep 2023 695th unfinishedprogram 655 70 10ms 27 Oct 2023 695th stefangimmillaro 655 70 9ms 12 Sep 2024 698th kevinmchung 654 81 10ms 1 Mar 2018 698th myfatemi04 654 81 10ms 1 Mar 2018 698th dzhang314 654 81 15ms 14 Aug 2019 698th glesnick 654 81 10ms 15 Jul 2022 698th ahmetdemirag 🇨🇾 654 81 10ms 8 Feb 2025 698th andrewjc2000 654 81 9ms 31 Jul 2025 704th lifthrasiir 🇰🇷 652 46 2ms 29 Nov 2024 705th Shanethegamer 🇺🇸 652 65 443ms 2 Jul 2021 706th Yewzir 🇧🇪 651 82 2ms 28 Mar 2024 707th commandz0 🇺🇸 650 75 526ms 15 Jan 2024 708th PsychoTea 650 96 359ms 21 Nov 2021 709th dokutan 647 113 6ms 2 Jul 2024 710th mathisfun271 646 82 17ms 13 Feb 2024 710th qpwoeirut 646 82 9ms 18 Sep 2025 712th inventshah 643 76 199ms 6 Jul 2022 713th marshallward 🇺🇸 643 94 39ms 8 Jul 2021 714th steffan-polygolf 642 76 465ms 7 Mar 2024 714th Jacob385 642 76 397ms 9 Apr 2024 716th Shanethegamer 🇺🇸 640 151 278ms 26 Mar 2022 717th dokutan 639 51 38ms 3 Nov 2024 718th elephantpanda 638 83 10ms 31 Aug 2022 719th MeWhenI 🇻🇦 637 100 1,358ms 19 Jun 2023 720th Shanethegamer 🇺🇸 636 165 62ms 25 Jul 2021 First Prev 641–720 of 2,084 Next Last