The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 7 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 800th DxSper 652 185 34ms 16 Feb 2024 800th driri85 652 185 30ms 16 Feb 2024 800th OCNeve 652 185 19ms 18 Jun 2024 800th croc54 652 185 21ms 31 Jan 2025 800th Alpha9584 652 185 20ms 20 Mar 2025 800th Hemanthred2005 652 185 25ms 3 May 2025 800th GodlyProgrammer1 652 185 25ms 28 Nov 2025 808th jared-hughes 651 141 14ms 10 Sep 2021 808th Andrey-Plotnikov 651 141 13ms 25 Oct 2024 810th Jonatan6 🇩🇰 651 157 11ms 4 Aug 2023 811th BlankSpruce 651 207 442ms 26 Aug 2022 812th HumanoidCPU 650 160 521ms 31 Oct 2024 812th KatieLG 🇬🇧 650 160 506ms 19 Apr 2025 814th HumanoidCPU 650 223 664ms 8 Nov 2025 815th Shanethegamer 🇺🇸 649 139 395ms 8 Jan 2022 816th TheAristos 649 186 30ms 21 Oct 2019 816th CorporalCrawdad 649 186 21ms 3 Oct 2024 818th lynn 648 185 30ms 23 Nov 2021 819th FlyingPenguin223 647 198 6ms 30 Nov 2024 820th uttumuttu 🇫🇮 646 142 25ms 4 Jan 2022 820th iliazeus 646 142 18ms 3 Sep 2022 820th LukeBridges 🇬🇧 646 142 14ms 28 Oct 2022 823rd Shanethegamer 🇺🇸 646 147 35ms 5 Nov 2022 824th TheZwierzLF 🇵🇱 646 161 591ms 13 Dec 2025 825th DialFrost 🇸🇬 645 140 471ms 25 May 2024 826th Yewzir 🇧🇪 645 165 225ms 13 Sep 2023 827th rowboat1 645 187 25ms 3 Apr 2021 827th rschwa6308 🇺🇸 645 187 66ms 18 Aug 2023 827th albanian-laundromat 645 187 21ms 24 Apr 2025 827th bogosorter 645 187 43ms 11 Jul 2025 827th celiendonze 🇨🇭 645 187 24ms 7 Nov 2025 832nd nsprd 645 209 456ms 19 Jan 2024 833rd MeWhenI 🇻🇦 643 159 10ms 25 Aug 2023 834th mamamia5x 642 143 18ms 8 Mar 2024 835th Yewzir 🇧🇪 642 162 566ms 21 Feb 2024 836th kevinmchung 642 188 35ms 2 Feb 2018 836th jhfranklin 🇬🇧 642 188 25ms 7 Mar 2021 836th ehulinsky 🇺🇸 642 188 20ms 8 May 2023 836th eiburns 642 188 20ms 3 Oct 2023 836th Just4FunCoder 642 188 40ms 18 Jun 2025 841st mtirado1 641 200 6ms 25 Dec 2022 842nd JGDoerrer 640 257 212ms 15 Feb 2022 843rd Waffle3z 639 128 60ms 17 Jan 2021 843rd hugolgst 639 128 43ms 4 Jun 2021 845th ay2718 639 189 29ms 14 Aug 2019 845th Kloppermand 🇩🇰 639 189 21ms 10 Jun 2020 845th martinnorling 🇸🇪 639 189 23ms 3 Mar 2022 845th ThijsLuttikhuis 639 189 28ms 3 Mar 2024 845th tri1212 🇻🇳 639 189 598ms 30 Jun 2024 845th emgordon154 639 189 31ms 24 Sep 2024 845th Mathrew2012 639 189 17ms 24 May 2025 852nd jared-hughes 639 211 415ms 24 Jun 2022 853rd kkoenig 639 244 320ms 30 Dec 2023 854th FireyFly 637 144 18ms 14 Apr 2018 854th KrausRaus 🇺🇸 637 144 16ms 23 Oct 2020 854th didion0 🇺🇸 637 144 13ms 22 Apr 2021 854th NewDefectus 🇮🇱 637 144 15ms 8 Oct 2021 854th raphaelimahorn 637 144 32ms 26 Oct 2022 859th emplv 🇱🇻 636 245 353ms 29 Apr 2024 860th LogicalJoe 635 190 34ms 24 May 2023 860th moustave 635 190 31ms 7 Apr 2025 862nd Babafaba 634 164 550ms 24 Nov 2025 863rd KatieLG 🇬🇧 633 143 1,620ms 17 Nov 2023 864th garrisonhh 632 191 20ms 21 Nov 2020 864th geofft 632 191 41ms 10 Dec 2020 864th CedricGebistorf 632 191 23ms 18 Feb 2022 864th Educorreia932 632 191 23ms 23 Jun 2022 864th Ripick 632 191 25ms 6 May 2023 864th anarconic 632 191 470ms 14 Dec 2023 864th jeff-re 632 191 22ms 6 May 2025 864th nemoyatpeace 632 191 26ms 8 Jan 2026 872nd emgordon154 631 152 158ms 15 Nov 2024 873rd albanian-laundromat 631 227 10ms 14 Jul 2025 874th MeWhenI 🇻🇦 630 169 228ms 16 Nov 2022 875th TeodorDyakov 🇧🇬 630 230 554ms 8 Jan 2026 876th okaponta 630 261 184ms 13 Jan 2024 877th Haksell 🇦🇶 629 130 54ms 5 Apr 2020 877th Natanaelel 🇸🇪 629 130 46ms 7 May 2025 879th emgordon154 629 181 3,365ms 9 Aug 2025 880th hellwue 629 192 22ms 22 Nov 2023 First Prev 801–880 of 1,910 Next Last