The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 40 hours. Why not try and solve them ahead of time?
Happy Numbers (Long) in all languages in bytes. 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 Bytes Time Submitted 469th DialFrost 🇸🇬 863 81 221ms 18 Dec 2023 469th edsrzf 🇳🇿 863 81 218ms 22 Jul 2025 469th Babafaba 863 81 306ms 6 Nov 2025 469th Flekay 🇩🇪 863 81 266ms 12 Feb 2026 469th dokutan 863 81 262ms 16 days ago 486th lifthrasiir 🇰🇷 862 29 5ms 29 Nov 2024 487th m-tkach 🇺🇦 862 81 3ms 6 Oct 2021 487th Steffan153 🇫🇮 862 81 3ms 12 Jan 2023 487th inventshah 862 81 3ms 14 Feb 2023 487th Alex-x90 🇺🇸 862 81 3ms 14 Feb 2023 487th JohandeRuiter 🇳🇱 862 81 4ms 8 Sep 2024 492nd stefangimmillaro 862 82 2,688ms 6 Nov 2024 492nd emgordon154 862 82 2,757ms 8 Nov 2024 492nd DialFrost 🇸🇬 862 82 2,589ms 19 Nov 2024 495th DialFrost 🇸🇬 861 87 36ms 12 Dec 2024 496th NewDefectus 🇮🇱 860 69 14ms 16 Dec 2021 496th Shanethegamer 🇺🇸 860 69 13ms 25 Apr 2023 496th KrausRaus 🇺🇸 860 69 17ms 6 Jan 2026 499th ovs-code 🇩🇪 860 96 460ms 29 Jul 2024 500th Shanethegamer 🇺🇸 860 98 4ms 20 Dec 2024 501st c0d3-4-F00d 🇩🇪 860 115 43ms 5 Jan 2022 501st MeWhenI 🇻🇦 860 115 43ms 21 Jun 2022 501st DialFrost 🇸🇬 860 115 44ms 28 Jan 2023 501st snoozingnewt 🇨🇦 860 115 43ms 16 Oct 2025 501st blaztoma 🇱🇹 860 115 44ms 23 Nov 2025 506th Shanethegamer 🇺🇸 859 93 151ms 20 Sep 2021 506th Yewzir 🇧🇪 859 93 138ms 27 Mar 2024 508th GolfingSuccess 🇬🇷 858 133 7ms 15 days ago 509th emgordon154 858 179 1,700ms 10 Jan 2026 510th DialFrost 🇸🇬 856 58 1,363ms 13 Apr 2025 511th GrayJoKing 🇦🇺 856 86 8ms 24 Feb 2026 512th edsrzf 🇳🇿 856 139 279ms 23 Oct 2024 513th GrayJoKing 🇦🇺 855 105 45ms 12 Mar 2022 514th Shanethegamer 🇺🇸 855 110 440ms 25 Sep 2025 514th Yewzir 🇧🇪 855 110 390ms 2 Oct 2025 514th CaedenHarper 🇨🇦 855 110 489ms 5 Nov 2025 514th MeWhenI 🇻🇦 855 110 461ms 7 Nov 2025 518th ovs-code 🇩🇪 854 89 15ms 30 Jun 2024 519th MeWhenI 🇻🇦 853 51 20ms 15 Feb 2025 520th akshatj27 🇦🇶 853 56 37ms 11 Jan 2022 520th m-tkach 🇺🇦 853 56 37ms 23 Feb 2023 522nd SirBogman 🇺🇸 853 82 215ms 21 Sep 2021 522nd stefangimmillaro 853 82 312ms 27 Sep 2021 522nd NewDefectus 🇮🇱 853 82 20ms 16 Dec 2021 522nd CedricGebistorf 853 82 228ms 25 Feb 2022 522nd Shanethegamer 🇺🇸 853 82 302ms 16 Dec 2022 522nd aksyristos 853 82 198ms 12 Feb 2023 522nd quimey 853 82 219ms 22 Mar 2023 522nd StefanHabel 🇨🇦 853 82 301ms 26 Mar 2023 522nd Fracture17 853 82 268ms 8 Apr 2023 522nd Re-Adventures 🇮🇳 853 82 216ms 20 Jul 2023 522nd Natanaelel 🇸🇪 853 82 217ms 29 Oct 2023 522nd Just4FunCoder 853 82 304ms 17 Feb 2024 522nd codingisgreatbutiamnot 853 82 300ms 25 Jul 2024 522nd lifthrasiir 🇰🇷 853 82 13ms 13 Nov 2024 522nd klixel 🇨🇦 853 82 300ms 17 Jan 2025 522nd blaztoma 🇱🇹 853 82 264ms 15 Nov 2025 522nd CommandLeo 🇮🇹 853 82 300ms 3 Dec 2025 522nd luuumine 🇫🇷 853 82 305ms 4 Dec 2025 522nd FortuiteMan 🇫🇷 853 82 296ms 5 Dec 2025 522nd FoxInTheClouds 853 82 218ms 13 Feb 2026 542nd lynn 853 115 28ms 21 Aug 2023 543rd MeWhenI 🇻🇦 852 72 95ms 13 Dec 2022 544th MeWhenI 🇻🇦 852 77 64ms 19 Sep 2021 544th snoozingnewt 🇨🇦 852 77 58ms 16 Oct 2025 546th inventshah 852 83 2,724ms 24 Oct 2024 546th aditsu 852 83 2,548ms 10 Aug 2025 548th snoozingnewt 🇨🇦 852 99 4ms 1 Sep 2024 549th The3gs 852 117 141ms 29 Nov 2024 550th Steffan153 🇫🇮 852 134 51ms 9 days ago 551st marcin7Cd 851 80 146ms 29 Sep 2021 551st cbrt-x 851 80 154ms 15 Sep 2023 553rd primo-ppcg 🇹🇭 851 82 1ms 22 Sep 2021 553rd nwellnhof 🇩🇪 851 82 2ms 22 Sep 2021 553rd Attero 🇸🇪 851 82 3ms 23 Dec 2021 553rd c0d3-4-F00d 🇩🇪 851 82 3ms 5 Jan 2022 553rd snoozingnewt 🇨🇦 851 82 3ms 13 Sep 2025 558th duckyluuk 🇳🇱 851 88 30ms 12 Dec 2024 558th GolfingSuccess 🇬🇷 851 88 23ms 11 Sep 2025 560th Lydxn 🇨🇦 851 90 40ms 20 Sep 2021 First Prev 481–560 of 2,106 Next Last