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?
DFA Simulator in all languages in chars. 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 Chars Time Submitted 401st Shanethegamer 🇺🇸 481 181 288ms 1 Nov 2023 402nd Yax42 🇫🇷 481 204 14ms 13 Feb 2026 403rd StefanHabel 🇨🇦 475 201 14ms 6 days ago 404th Code-Coder-coder 473 202 13ms 9 Feb 2026 405th snoozingnewt 🇨🇦 470 307 366ms 18 Oct 2025 406th jerrandolph 470 438 296ms 1 Nov 2023 407th Shanethegamer 🇺🇸 469 180 6ms 9 Nov 2023 408th Babafaba 465 193 406ms 17 Nov 2025 409th janbehrens 🇩🇪 464 190 427ms 9 Jan 2024 410th Pyroan 464 206 12ms 12 Mar 2025 411th MeWhenI 🇻🇦 463 188 295ms 7 Dec 2023 412th CaedenHarper 🇨🇦 461 208 1,172ms 20 Sep 2025 413th MeWhenI 🇻🇦 460 189 173ms 3 Aug 2024 414th roguh 🇬🇹 460 324 2ms 15 Oct 2024 415th Lv0Sys 🇵🇱 459 364 583ms 22 days ago 416th MeWhenI 🇻🇦 458 308 9ms 27 Jun 2024 417th snoozingnewt 🇨🇦 456 157 36ms 18 Oct 2025 418th hiichbindermax 453 211 11ms 20 Nov 2023 418th thienudomsrirungruang 453 211 11ms 1 Apr 2024 420th YAJUE114514 448 213 10ms 10 Dec 2025 421st VictorFordham 444 215 13ms 24 Nov 2023 422nd alemelis 441 200 1,470ms 20 Sep 2024 423rd CaedenHarper 🇨🇦 438 218 18ms 21 Sep 2025 424th amollberg 🇸🇪 434 220 12ms 14 Jan 2024 425th MeWhenI 🇻🇦 434 221 1,108ms 30 Aug 2025 426th snoozingnewt 🇨🇦 427 323 126ms 18 Oct 2025 427th jgbaldwinbrown 427 349 2ms 14 Mar 2024 428th snoozingnewt 🇨🇦 427 395 3,095ms 18 Oct 2025 429th blaztoma 🇱🇹 427 453 112ms 28 Nov 2025 430th snoozingnewt 🇨🇦 422 267 3ms 18 Oct 2025 431st Ripick 418 211 386ms 28 Jun 2025 432nd CaedenHarper 🇨🇦 417 215 521ms 21 Sep 2025 433rd CaedenHarper 🇨🇦 416 236 10ms 15 Sep 2025 434th IISResetMe 415 210 839ms 2 Dec 2025 435th jtaxen 415 230 12ms 8 Jun 2024 436th snoozingnewt 🇨🇦 413 457 35ms 18 Oct 2025 437th snoozingnewt 🇨🇦 408 207 4ms 18 Oct 2025 438th alemelis 408 234 32ms 11 Oct 2024 439th Schmitt-Very-Cool 408 462 472ms 26 Sep 2025 440th croc54 405 236 11ms 17 Dec 2024 441st dokutan 401 220 1,015ms 7 Mar 2024 442nd fgrosshans 🇫🇷 400 239 13ms 7 Nov 2023 443rd jameswmccarty 398 240 12ms 24 Feb 2025 443rd Heathcorp 🇦🇺 398 240 11ms 12 Aug 2025 445th snoozingnewt 🇨🇦 398 247 10ms 18 Oct 2025 446th adoxography 396 241 12ms 19 Nov 2023 447th snoozingnewt 🇨🇦 395 492 44ms 18 Oct 2025 448th tomh1012 388 246 12ms 21 days ago 449th neihousaigaai 387 247 12ms 7 Oct 2024 450th retrohun 385 339 56ms 18 Nov 2023 451st CaedenHarper 🇨🇦 385 489 410ms 7 Oct 2025 452nd galloj 🇨🇿 376 254 11ms 24 Nov 2023 452nd MaxElf999 376 254 13ms 9 Feb 2024 454th snoozingnewt 🇨🇦 372 418 198ms 18 Oct 2025 455th snoozingnewt 🇨🇦 369 354 46ms 18 Oct 2025 456th msbranicky 369 413 17ms 1 Nov 2023 457th MeWhenI 🇻🇦 368 355 121ms 18 Nov 2023 458th logvp 366 261 12ms 6 Oct 2024 459th za3k 365 262 12ms 22 Jul 2025 460th msbranicky 365 563 299ms 1 Nov 2023 461st zakariamouhid 356 276 14ms 1 Nov 2023 462nd msbranicky 356 462 11ms 1 Nov 2023 463rd BREMAUCY 🇫🇷 354 270 13ms 21 Aug 2025 464th JDiLenarda 🇫🇷 353 490 1,405ms 13 Sep 2024 465th FortuiteMan 🇫🇷 351 272 13ms 14 Oct 2024 466th Lv0Sys 🇵🇱 349 281 13ms 27 days ago 467th arcpolaris 349 409 498ms 13 Jan 2026 468th KatieLG 🇬🇧 348 740 18ms 25 Aug 2024 469th alexjurkiewicz 🇦🇺 347 275 12ms 14 Nov 2023 470th FranklinJiaChen 344 278 13ms 4 Jul 2024 471st Xzyaihni 344 607 231ms 1 Nov 2023 472nd BREMAUCY 🇫🇷 336 267 624ms 21 Aug 2025 473rd TheZwierzLF 🇵🇱 334 286 32ms 5 Jan 2026 474th madex 🇩🇪 334 625 332ms 8 Oct 2025 475th jelleromer 329 290 25ms 19 Nov 2023 476th snoozingnewt 🇨🇦 329 574 132ms 18 Oct 2025 477th msbranicky 329 633 244ms 1 Nov 2023 478th CaedenHarper 🇨🇦 327 436 437ms 17 Oct 2025 479th TheZwierzLF 🇵🇱 324 221 58ms 6 Jan 2026 480th snoozingnewt 🇨🇦 324 364 2ms 18 Oct 2025 First Prev 401–480 of 520 Next Last