The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 3 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 801st Maltaran 🇵🇱 653 122 54ms 4 days ago 802nd Shanethegamer 🇺🇸 653 163 175ms 24 May 2025 803rd nsprd 652 185 25ms 19 Jan 2024 803rd DxSper 652 185 34ms 16 Feb 2024 803rd driri85 652 185 30ms 16 Feb 2024 803rd OCNeve 652 185 19ms 18 Jun 2024 803rd croc54 652 185 21ms 31 Jan 2025 803rd Alpha9584 652 185 20ms 20 Mar 2025 803rd Hemanthred2005 652 185 25ms 3 May 2025 803rd GodlyProgrammer1 652 185 25ms 28 Nov 2025 811th jared-hughes 651 141 25ms 10 Sep 2021 811th Andrey-Plotnikov 651 141 13ms 25 Oct 2024 813th Jonatan6 🇩🇰 651 157 11ms 4 Aug 2023 814th BlankSpruce 651 207 463ms 26 Aug 2022 815th HumanoidCPU 650 160 521ms 31 Oct 2024 815th KatieLG 🇬🇧 650 160 506ms 19 Apr 2025 817th HumanoidCPU 650 223 664ms 8 Nov 2025 818th Shanethegamer 🇺🇸 649 139 395ms 8 Jan 2022 819th TheAristos 649 186 30ms 21 Oct 2019 819th CorporalCrawdad 649 186 21ms 3 Oct 2024 821st lynn 648 185 30ms 23 Nov 2021 822nd FlyingPenguin223 647 198 6ms 30 Nov 2024 823rd uttumuttu 🇫🇮 646 142 26ms 4 Jan 2022 823rd iliazeus 646 142 19ms 3 Sep 2022 823rd LukeBridges 🇬🇧 646 142 23ms 28 Oct 2022 826th Shanethegamer 🇺🇸 646 147 35ms 5 Nov 2022 827th TheZwierzLF 🇵🇱 646 161 591ms 13 Dec 2025 828th DialFrost 🇸🇬 645 140 471ms 25 May 2024 829th Yewzir 🇧🇪 645 165 225ms 13 Sep 2023 830th rowboat1 645 187 25ms 3 Apr 2021 830th rschwa6308 🇺🇸 645 187 66ms 18 Aug 2023 830th albanian-laundromat 645 187 21ms 24 Apr 2025 830th bogosorter 645 187 43ms 11 Jul 2025 830th celiendonze 🇨🇭 645 187 24ms 7 Nov 2025 835th nsprd 645 209 501ms 19 Jan 2024 836th MeWhenI 🇻🇦 643 159 10ms 25 Aug 2023 837th mamamia5x 642 143 14ms 8 Mar 2024 838th Yewzir 🇧🇪 642 162 566ms 21 Feb 2024 839th kevinmchung 642 188 35ms 2 Feb 2018 839th jhfranklin 🇬🇧 642 188 25ms 7 Mar 2021 839th ehulinsky 🇺🇸 642 188 20ms 8 May 2023 839th eiburns 642 188 20ms 3 Oct 2023 839th Just4FunCoder 642 188 40ms 18 Jun 2025 844th mtirado1 641 200 6ms 25 Dec 2022 845th JGDoerrer 641 257 182ms 15 Feb 2022 846th Waffle3z 639 128 60ms 17 Jan 2021 846th hugolgst 639 128 43ms 4 Jun 2021 848th ay2718 639 189 29ms 14 Aug 2019 848th Kloppermand 🇩🇰 639 189 21ms 10 Jun 2020 848th martinnorling 🇸🇪 639 189 23ms 3 Mar 2022 848th ThijsLuttikhuis 639 189 28ms 3 Mar 2024 848th tri1212 🇻🇳 639 189 598ms 30 Jun 2024 848th emgordon154 639 189 31ms 24 Sep 2024 848th Mathrew2012 639 189 17ms 24 May 2025 855th jared-hughes 639 211 477ms 24 Jun 2022 856th kkoenig 639 244 320ms 30 Dec 2023 857th FireyFly 637 144 20ms 14 Apr 2018 857th KrausRaus 🇺🇸 637 144 23ms 23 Oct 2020 857th didion0 🇺🇸 637 144 15ms 22 Apr 2021 857th NewDefectus 🇮🇱 637 144 16ms 8 Oct 2021 857th raphaelimahorn 637 144 17ms 26 Oct 2022 862nd emplv 🇱🇻 636 245 353ms 29 Apr 2024 863rd LogicalJoe 635 190 34ms 24 May 2023 863rd moustave 635 190 31ms 7 Apr 2025 865th Babafaba 634 164 550ms 24 Nov 2025 866th KatieLG 🇬🇧 633 143 1,620ms 17 Nov 2023 867th garrisonhh 632 191 20ms 21 Nov 2020 867th geofft 632 191 41ms 10 Dec 2020 867th CedricGebistorf 632 191 23ms 18 Feb 2022 867th Educorreia932 632 191 23ms 23 Jun 2022 867th Ripick 632 191 25ms 6 May 2023 867th anarconic 632 191 470ms 14 Dec 2023 867th jeff-re 632 191 22ms 6 May 2025 867th nemoyatpeace 632 191 26ms 8 Jan 2026 875th emgordon154 631 152 158ms 15 Nov 2024 876th albanian-laundromat 631 227 10ms 14 Jul 2025 877th okaponta 631 261 202ms 13 Jan 2024 878th TeodorDyakov 🇧🇬 630 230 554ms 8 Jan 2026 879th Haksell 🇦🇶 629 130 54ms 5 Apr 2020 879th Natanaelel 🇸🇪 629 130 46ms 7 May 2025 First Prev 801–880 of 1,913 Next Last