The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 25 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 721st janbehrens 🇩🇪 813 73 10ms 20 Sep 2021 721st didion0 🇺🇸 813 73 43ms 23 Nov 2021 721st KatieLG 🇬🇧 813 73 14ms 5 Apr 2022 721st emgordon154 813 73 10ms 7 Nov 2024 725th andre-lameirinhas 🇵🇹 813 86 187ms 4 Nov 2021 725th RYNO8 813 86 62ms 16 Aug 2022 725th LeeCamp 813 86 220ms 15 Jan 2023 725th vishwathg 813 86 363ms 4 Feb 2023 725th cros107 🇦🇺 813 86 251ms 11 Oct 2023 725th logvp 813 86 3,516ms 12 Jan 2024 725th Bmrl7 813 86 15ms 29 Feb 2024 725th Grrisly 813 86 265ms 29 Mar 2024 725th SB-945 813 86 20ms 31 Mar 2024 725th resoNathan 813 86 12ms 18 Jul 2024 725th Andrey2001 813 86 13ms 4 Dec 2025 725th JOrE20 813 86 20ms 17 Feb 2026 725th madex 🇩🇪 813 86 20ms 15 days ago 738th Natanaelel 🇸🇪 811 33 69ms 22 Jul 2022 738th SirBogman 🇺🇸 811 33 70ms 10 Sep 2022 740th MeWhenI 🇻🇦 811 71 64ms 5 Apr 2025 741st AlephSquirrel 811 104 4ms 6 Aug 2024 742nd GolfingSuccess 🇬🇷 810 117 60ms 19 Mar 2025 743rd OhmNomNom 809 59 36ms 20 Oct 2022 743rd AlephSquirrel 809 59 68ms 14 Apr 2023 743rd SirBogman 🇺🇸 809 59 73ms 10 Jan 2024 743rd error256 809 59 52ms 13 May 2024 747th MeWhenI 🇻🇦 808 93 18ms 2 Oct 2022 748th Shanethegamer 🇺🇸 808 100 11ms 10 Sep 2022 748th albanian-laundromat 808 100 11ms 24 Dec 2025 750th NewDefectus 🇮🇱 807 54 61ms 15 Dec 2021 750th LostSyntax21 🇬🇧 807 54 145ms 8 Jan 2025 752nd Yewzir 🇧🇪 807 83 587ms 15 Jan 2024 753rd MeWhenI 🇻🇦 807 90 2ms 10 Oct 2023 754th Shanethegamer 🇺🇸 806 31 6ms 13 Jan 2022 755th AlephSquirrel 805 89 13ms 20 Apr 2023 756th frankgraziano 805 232 37ms 31 Oct 2025 757th scpchicken 🇵🇼 804 87 230ms 12 Jan 2022 757th JuliaSzulc 804 87 20ms 16 Mar 2022 757th LHuitre 804 87 21ms 5 Jun 2022 757th betaveros 804 87 383ms 1 Jan 2023 757th croc54 804 87 249ms 8 Jan 2025 757th LostSyntax21 🇬🇧 804 87 208ms 8 Mar 2025 757th andrewjc2000 804 87 19ms 11 Aug 2025 764th jared-hughes 804 124 127ms 10 Nov 2022 764th Re-Adventures 🇮🇳 804 124 133ms 22 Jun 2023 766th snoozingnewt 🇨🇦 804 148 284ms 4 Feb 2024 767th snoozingnewt 🇨🇦 803 66 14ms 1 Sep 2024 767th LostSyntax21 🇬🇧 803 66 3ms 8 Jan 2025 769th Steffan153 🇫🇮 803 95 21ms 21 Feb 2023 769th Waffle3z 803 95 2ms 26 Dec 2025 771st error256 803 117 403ms 17 days ago 772nd tailorspy 803 118 66ms 22 Sep 2024 772nd dokutan 803 118 65ms 6 Nov 2025 774th GrayJoKing 🇦🇺 802 72 162ms 3 Aug 2024 775th c0d3-4-F00d 🇩🇪 802 74 13ms 5 Jan 2022 775th Maznek 802 74 11ms 19 Jun 2023 775th thisishowmymindworks 🇳🇴 802 74 116ms 9 Jun 2024 775th snoozingnewt 🇨🇦 802 74 11ms 1 Sep 2024 775th blaztoma 🇱🇹 802 74 10ms 23 Nov 2025 780th brimstonetrader 801 85 122ms 26 Jan 2024 781st Natanaelel 🇸🇪 800 72 71ms 26 Sep 2023 782nd inventshah 800 158 415ms 8 Sep 2022 783rd Shanethegamer 🇺🇸 799 105 15ms 17 Dec 2023 784th primo-ppcg 🇹🇭 798 61 1,387ms 9 Feb 2022 785th msbranicky 798 91 3ms 11 Oct 2023 786th LostSyntax21 🇬🇧 798 149 287ms 8 Jan 2025 787th DialFrost 🇸🇬 797 63 245ms 21 Jan 2025 788th ovs-code 🇩🇪 797 66 10ms 15 Aug 2024 788th sisyphus-ppcg 🇦🇺 797 66 14ms 19 Aug 2024 790th Alessandro-Balconi 🇮🇹 797 77 96ms 14 Jul 2023 791st MeWhenI 🇻🇦 797 100 111ms 15 Oct 2022 792nd namelessiw 797 118 508ms 6 Oct 2025 793rd emplv 🇱🇻 797 148 24ms 29 Jun 2022 794th Shanethegamer 🇺🇸 796 60 100ms 19 Sep 2021 794th adoxography 796 60 39ms 18 Dec 2021 794th jared-hughes 796 60 38ms 9 Sep 2022 794th Lv0Sys 🇵🇱 796 60 36ms 5 Dec 2025 798th Herbert00709 🇵🇱 796 119 61ms 4 Sep 2024 798th error256 796 119 62ms 22 Feb 2026 800th Waffle3z 795 88 19ms 19 Sep 2021 First Prev 721–800 of 2,106 Next Last