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?
Catalan 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 705th Stockoh 🇫🇷 840 51 12ms 14 Jun 2024 705th bac0id 840 51 10ms 29 Jun 2024 705th abhishekg999 840 51 10ms 20 Sep 2024 705th Hyunwook-Kim-WV 840 51 10ms 7 Aug 2025 705th jacekwladzinski 840 51 10ms 2 Oct 2025 705th 77Tigers 840 51 9ms 13 Jan 2026 705th zzz13579zzz 840 51 9ms 29 Jan 2026 705th madex 🇩🇪 840 51 10ms 9 days ago 705th Matter1024 🇮🇳 840 51 10ms 48 mins ago 730th UnderKoen 🇳🇱 839 382 271ms 20 Jun 2025 731st neel11235813 838 44 430ms 15 Jan 2024 731st rucin93 🇵🇱 838 44 410ms 19 Jan 2024 731st SirBogman 🇺🇸 838 44 429ms 20 Jan 2024 731st AlephSquirrel 838 44 394ms 21 Jan 2024 731st ndren 838 44 339ms 8 Feb 2026 736th emplv 🇱🇻 838 140 285ms 16 Nov 2022 737th GrayJoKing 🇦🇺 838 179 43ms 28 Jun 2022 738th MeWhenI 🇻🇦 836 42 949ms 30 Aug 2025 739th Yewzir 🇧🇪 836 61 3ms 7 May 2024 740th thisishowmymindworks 🇳🇴 835 47 10ms 11 Jun 2023 740th Babafaba 835 47 10ms 22 Oct 2025 742nd cbrt-x 833 55 121ms 19 Sep 2023 743rd MeWhenI 🇻🇦 832 76 112ms 15 Oct 2022 744th Yewzir 🇧🇪 832 135 1,853ms 14 Nov 2025 745th aksyristos 830 37 36ms 4 Mar 2023 745th aydamak 830 37 35ms 7 May 2024 747th janbehrens 🇩🇪 830 75 469ms 24 Apr 2023 747th Yewzir 🇧🇪 830 75 508ms 7 May 2024 749th Waffle3z 830 144 2ms 8 Apr 2022 750th DialFrost 🇸🇬 829 49 78ms 15 Nov 2024 750th jipsong 🇩🇪 829 49 71ms 12 Feb 2025 752nd voytxt 🇨🇿 829 51 130ms 3 Aug 2024 752nd dokutan 829 51 132ms 14 Feb 2026 754th DialFrost 🇸🇬 828 94 208ms 8 Jan 2026 755th snoozingnewt 🇨🇦 828 131 476ms 3 Dec 2025 756th Steffan153 🇫🇮 827 43 32ms 7 Oct 2022 756th DialFrost 🇸🇬 827 43 30ms 11 Feb 2023 756th Shanethegamer 🇺🇸 827 43 31ms 21 Feb 2023 756th o0lit3 🇺🇸 827 43 31ms 8 Jun 2023 756th sean-niemann 🇺🇸 827 43 31ms 21 Sep 2025 761st Ripick 827 64 5ms 14 Mar 2024 762nd DialFrost 🇸🇬 826 82 2,696ms 26 Oct 2024 763rd GrayJoKing 🇦🇺 826 186 17ms 1 Aug 2023 764th dokutan 826 1,102 21ms 3 days ago 765th edsrzf 🇳🇿 824 47 64ms 9 Dec 2025 766th Herbert00709 🇵🇱 824 52 9ms 21 Feb 2024 766th namelessiw 824 52 11ms 19 Aug 2024 766th WillowWispy 824 52 10ms 13 Mar 2025 769th ovs-code 🇩🇪 824 114 1,414ms 29 Mar 2025 770th stefangimmillaro 821 77 109ms 30 Sep 2023 771st lifthrasiir 🇰🇷 819 45 446ms 2 Dec 2024 772nd daniel-pedersen 🇸🇪 818 48 11ms 6 Mar 2022 773rd Awsute 818 56 122ms 21 Apr 2022 773rd yzhs 🇩🇪 818 56 121ms 16 Jun 2022 775th ovs-code 🇩🇪 818 140 6ms 25 Nov 2024 776th dokutan 817 45 249ms 19 May 2024 776th Ripick 817 45 284ms 27 Jun 2025 776th JOrE20 817 45 213ms 23 Feb 2026 776th denkyuu1 817 45 255ms 32 hours ago 780th edsrzf 🇳🇿 817 115 1,431ms 18 Jan 2025 780th error256 817 115 1,451ms 5 Feb 2025 782nd CornerMercury 🇬🇧 815 75 114ms 27 Nov 2025 783rd Herbert00709 🇵🇱 814 135 95ms 3 Apr 2025 784th CaedenHarper 🇨🇦 813 22 41ms 7 days ago 785th Yewzir 🇧🇪 812 61 1,343ms 7 May 2024 786th lynn 812 148 138ms 12 Jan 2025 787th ZakkkkAttackkkk 🇵🇭 809 53 10ms 30 Jan 2022 787th iakolzin 809 53 10ms 27 May 2022 787th nullie 809 53 10ms 7 Jun 2022 787th yzhs 🇩🇪 809 53 10ms 22 Jun 2022 787th markusgraube 809 53 11ms 24 Apr 2023 787th mstang107 809 53 10ms 20 Dec 2023 787th smokestacklightnin 🇺🇸 809 53 9ms 10 Jan 2024 787th HumanoidCPU 809 53 16ms 27 May 2024 787th Mabeloid 🇳🇴 809 53 9ms 21 Sep 2024 787th agreegious 809 53 12ms 14 Nov 2024 787th 0dyse 809 53 10ms 29 Apr 2025 787th piano-miles 809 53 10ms 9 May 2025 787th poodletricea 809 53 10ms 9 Jan 2026 787th TheSecondComing123 809 53 10ms 4 Feb 2026 First Prev 721–800 of 2,051 Next Last