The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 8 days. Why not try and solve them ahead of time?
Emirp Numbers 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 641st rucin93 🇵🇱 823 66 141ms 5 Jan 2025 641st sean-niemann 🇺🇸 823 66 142ms 19 May 2025 643rd Yewzir 🇧🇪 823 149 78ms 81 mins ago 644th MeWhenI 🇻🇦 821 40 47ms 23 Jul 2022 644th AlephSquirrel 821 40 45ms 31 Jul 2022 646th handisb 821 69 36ms 25 Oct 2019 646th olivermrose 🇺🇸 821 69 37ms 31 Oct 2021 648th StanislavNikolov 821 80 10ms 26 Nov 2017 648th jacklynnepenick 821 80 59ms 16 Aug 2021 648th ejini6969 821 80 12ms 1 Apr 2023 648th TheSecondComing123 821 80 10ms 4 Feb 2026 652nd DialFrost 🇸🇬 821 87 1,021ms 26 Feb 2025 653rd MeWhenI 🇻🇦 821 117 56ms 29 Nov 2022 653rd Alex-x90 🇺🇸 821 117 59ms 28 Jan 2023 655th GalladeGuy 🇺🇸 819 82 2ms 21 May 2020 656th PatrickStephansen 🇿🇦 818 78 10ms 16 Oct 2020 656th Shanethegamer 🇺🇸 818 78 10ms 19 Apr 2022 658th JDiLenarda 🇫🇷 817 91 1,398ms 9 Oct 2020 659th fuzzylojik-golf 🇺🇸 817 101 397ms 31 Aug 2025 659th amazingalek 🇳🇴 817 101 458ms 6 Jan 2026 661st AshyIsMe 🇦🇺 816 35 34ms 4 Aug 2022 662nd Irratix 🇳🇱 816 57 2ms 12 Dec 2021 663rd primo-ppcg 🇹🇭 816 115 125ms 2 May 2022 664th MeWhenI 🇻🇦 814 74 3ms 12 Aug 2024 664th DialFrost 🇸🇬 814 74 4ms 16 Aug 2024 664th Shanethegamer 🇺🇸 814 74 3ms 25 May 2025 664th snoozingnewt 🇨🇦 814 74 3ms 30 Nov 2025 668th KatieLG 🇬🇧 814 77 434ms 15 Jan 2024 668th Babafaba 814 77 476ms 17 Nov 2025 670th Waffle3z 811 81 10ms 7 Sep 2021 670th quimey 811 81 17ms 21 Jun 2023 672nd GoateSo 810 83 2ms 14 Aug 2023 673rd prplz 🇦🇺 810 122 24ms 10 Jul 2021 674th eldritchconundrum 809 70 36ms 31 Oct 2022 675th BBoehm 🇩🇪 808 79 10ms 20 Jan 2021 675th DialFrost 🇸🇬 808 79 10ms 14 Nov 2023 677th lifthrasiir 🇰🇷 806 31 2ms 29 Nov 2024 677th GrayJoKing 🇦🇺 806 31 2ms 26 Jun 2025 679th Yewzir 🇧🇪 806 117 363ms 2 Oct 2025 680th scpchicken 🇵🇼 804 59 3ms 5 Feb 2023 681st weeble 803 75 3ms 16 Dec 2024 682nd prplz 🇦🇺 802 117 130ms 30 Apr 2022 683rd SirBogman 🇺🇸 801 41 45ms 29 Oct 2022 683rd CaedenHarper 🇨🇦 801 41 48ms 5 days ago 685th Powerroff 801 82 24ms 10 Nov 2024 686th gastropner 801 103 1ms 5 Jan 2021 686th janbehrens 🇩🇪 801 103 376ms 20 Jun 2023 688th dokutan 801 120 58ms 14 Apr 2024 688th snyderek 🇺🇸 801 120 56ms 17 Oct 2024 690th msbranicky 799 135 294ms 8 Sep 2023 691st annaproxy 798 71 36ms 27 Aug 2022 692nd handisb 798 80 11ms 25 Oct 2019 692nd marcin7Cd 798 80 10ms 5 Oct 2020 692nd stefangimmillaro 798 80 9ms 27 Aug 2022 695th Lydxn 🇨🇦 798 99 2ms 11 Oct 2023 696th dokutan 798 115 40ms 28 Aug 2024 696th MeWhenI 🇻🇦 798 115 40ms 30 Aug 2024 696th pardouin 🇫🇷 798 115 41ms 23 Sep 2024 699th MeWhenI 🇻🇦 797 93 36ms 28 Jun 2022 700th kaascevich 797 95 92ms 21 Jul 2025 701st m-tkach 🇺🇦 797 124 25ms 18 Jun 2022 702nd dokutan 796 118 123ms 14 Apr 2024 703rd janbehrens 🇩🇪 795 70 247ms 28 Nov 2023 704th MeWhenI 🇻🇦 794 84 2,653ms 24 Oct 2024 705th jared-hughes 793 36 33ms 23 Sep 2021 705th 4hg 🇺🇸 793 36 34ms 11 Mar 2025 707th SirBogman 🇺🇸 793 79 406ms 15 Jan 2024 708th GrayJoKing 🇦🇺 793 81 2,261ms 30 Mar 2021 709th dokutan 793 119 369ms 24 Sep 2025 710th yanqui-uxo 792 95 150ms 14 Sep 2018 710th GrayJoKing 🇦🇺 792 95 150ms 16 Mar 2021 710th Natanaelel 🇸🇪 792 95 145ms 11 Sep 2021 710th stackofbears 792 95 151ms 7 Oct 2023 710th HolmDev 792 95 138ms 10 Sep 2025 715th retrohun 790 49 127ms 26 Apr 2019 716th Yewzir 🇧🇪 790 98 120ms 28 Mar 2024 717th DialFrost 🇸🇬 790 100 2ms 18 Nov 2025 718th m-tkach 🇺🇦 790 115 27ms 18 Jan 2024 719th primo-ppcg 🇹🇭 790 176 1,696ms 15 Sep 2025 720th rak1507 🇬🇧 788 59 2ms 1 Nov 2020 First Prev 641–720 of 3,203 Next Last