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?
Arabic to Roman 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 blaztoma 🇱🇹 705 116 63ms 13 Oct 2025 642nd billings7 🇬🇧 705 169 384ms 21 Nov 2021 643rd primo-ppcg 🇹🇭 704 206 597ms 2 Sep 2020 643rd h3ra993huskp 🇯🇵 704 206 586ms 30 Nov 2025 645th angel-p57 🇯🇵 704 238 12ms 18 May 2022 646th commandz0 🇺🇸 703 148 597ms 1 Sep 2025 647th aditsu 703 162 3,343ms 9 Sep 2025 648th minus7 702 172 20ms 24 Feb 2018 648th cubed-guy 702 172 24ms 2 Nov 2022 648th adamnielson42 🇺🇸 702 172 22ms 7 Dec 2023 648th CutSandstone 702 172 18ms 4 Jul 2024 652nd stefangimmillaro 702 222 334ms 24 Oct 2023 653rd lifthrasiir 🇰🇷 701 63 8ms 30 Nov 2024 654th PatrickStephansen 🇿🇦 700 131 24ms 19 Oct 2020 654th voytxt 🇨🇿 700 131 16ms 20 Jul 2025 656th ethanlally 700 207 483ms 8 Jan 2026 657th Betuaredead 699 69 15ms 12 Jan 2023 658th declank 699 117 53ms 21 days ago 659th frankgraziano 699 356 215ms 7 Nov 2025 660th SirBogman 🇺🇸 698 117 1,257ms 11 Apr 2024 661st inventshah 698 149 422ms 22 Jan 2024 662nd yokasuretsu 698 173 23ms 14 Jan 2025 663rd tobeannouncd 698 209 332ms 3 Jan 2024 664th retrohun 696 137 1,222ms 29 Oct 2019 665th duckyluuk 🇳🇱 695 181 60ms 16 Dec 2024 666th MaxElf999 694 174 27ms 29 Sep 2022 666th Pyroan 694 174 21ms 5 Jan 2026 668th jmerle 🇳🇱 693 96 80ms 5 Jul 2023 668th f-tucker 693 96 83ms 19 Dec 2023 670th jared-hughes 693 118 42ms 12 Sep 2022 671st Shanethegamer 🇺🇸 693 150 490ms 17 Jan 2024 672nd HumanoidCPU 693 218 124ms 10 Jun 2024 673rd GrayJoKing 🇦🇺 691 167 142ms 26 Jan 2023 674th AlephSquirrel 690 133 16ms 15 Feb 2023 674th niklv 🇷🇺 690 133 18ms 21 Dec 2023 674th jbt 690 133 16ms 25 Dec 2023 677th LouisRustenholz 690 175 46ms 23 Dec 2021 677th wrose100 690 175 25ms 9 Apr 2022 677th yoavjs 690 175 18ms 1 Apr 2025 677th Babafaba 690 175 22ms 24 Nov 2025 677th dokutan 690 175 25ms 1 Feb 2026 677th Matter1024 🇮🇳 690 175 20ms 5 hours ago 683rd MeWhenI 🇻🇦 689 151 483ms 24 May 2024 684th acornellier 687 119 51ms 11 Dec 2018 685th DialFrost 🇸🇬 687 155 187ms 24 May 2025 686th mossprescott 686 176 19ms 24 Jun 2019 686th NanduBC 686 176 26ms 17 Mar 2021 686th za3k 686 176 23ms 11 Oct 2022 686th QuincyNash 🇺🇸 686 176 409ms 4 Dec 2022 686th msbranicky 686 176 21ms 27 Jul 2023 686th fkantelberg 686 176 25ms 9 Aug 2023 686th ssbhatt4321 686 176 31ms 14 Oct 2023 686th JorgiEagle 686 176 21ms 8 Feb 2024 686th hiichbindermax 686 176 26ms 11 Sep 2024 695th kimbo 🇺🇸 686 227 371ms 17 Dec 2022 696th fgrosshans 🇫🇷 685 97 82ms 5 May 2023 697th janbehrens 🇩🇪 685 134 13ms 12 Nov 2023 698th MeWhenI 🇻🇦 685 140 153ms 3 Aug 2024 699th makononov 685 240 281ms 28 Feb 2025 700th timvermeulen 684 221 110ms 19 Jan 2020 701st MeWhenI 🇻🇦 683 228 338ms 17 Apr 2023 702nd jmerle 🇳🇱 682 177 21ms 20 Jun 2023 702nd SB-945 682 177 24ms 3 Mar 2024 702nd drochom 682 177 20ms 20 Jun 2024 702nd vhoulbreque 🇫🇷 682 177 22ms 13 Sep 2025 702nd CaedenHarper 🇨🇦 682 177 43ms 29 Oct 2025 707th KatieLG 🇬🇧 681 120 41ms 16 Nov 2023 708th Yewzir 🇧🇪 681 175 458ms 19 Jun 2024 709th DaCuteRaccoon 680 71 14ms 3 Dec 2022 710th MeWhenI 🇻🇦 680 120 852ms 29 Jan 2023 711th SirBogman 🇺🇸 680 153 615ms 16 Jan 2024 711th duckyluuk 🇳🇱 680 153 582ms 7 Jul 2025 713th lynn 680 216 188ms 17 Jul 2023 714th janbehrens 🇩🇪 678 133 1,008ms 1 Nov 2021 715th stefangimmillaro 678 168 3,752ms 10 Nov 2024 715th MeWhenI 🇻🇦 678 168 3,186ms 2 Dec 2024 717th snooze92 🇫🇷 678 178 22ms 26 Feb 2025 717th milana-94888u 678 178 20ms 5 Mar 2025 717th InigoK 🇺🇸 678 178 27ms 26 Aug 2025 720th edsrzf 🇳🇿 678 180 474ms 22 Jul 2025 First Prev 641–720 of 1,909 Next Last