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 321st rucin93 🇵🇱 603 144 164ms 23 days ago 322nd jared-hughes 603 247 2ms 18 Aug 2024 323rd helbling 🇨🇭 602 163 11ms 23 Sep 2024 324th olleicua 🇺🇸 601 119 41ms 15 Jan 2024 325th mathisfun271 601 159 12ms 19 Feb 2024 326th Mandrzejy 🇵🇱 600 281 73ms 19 Jul 2024 327th MeWhenI 🇻🇦 598 150 594ms 24 May 2024 328th GolfingSuccess 🇬🇷 597 160 12ms 1 Nov 2023 328th MichalMarsalek 🇨🇿 597 160 12ms 1 Nov 2023 330th Shanethegamer 🇺🇸 596 120 40ms 1 Nov 2023 331st dylanarmstrong 595 165 10ms 22 Jan 2024 332nd GolfingSuccess 🇬🇷 594 151 556ms 20 Jan 2024 332nd MichalMarsalek 🇨🇿 594 151 544ms 21 Jan 2024 334th jared-hughes 593 161 12ms 2 Nov 2023 335th MeWhenI 🇻🇦 592 285 1,413ms 1 Nov 2023 336th Mandrzejy 🇵🇱 591 252 2ms 8 Jul 2024 337th annaproxy 590 162 13ms 1 Nov 2023 337th 5cw 🇺🇸 590 162 11ms 1 Nov 2023 337th edsrzf 🇳🇿 590 162 11ms 29 Jun 2025 340th MeWhenI 🇻🇦 588 167 10ms 1 Nov 2023 341st MeWhenI 🇻🇦 588 180 138ms 26 Sep 2024 342nd AlephSquirrel 586 153 557ms 22 Jan 2024 343rd stefangimmillaro 586 163 16ms 29 Sep 2024 344th MeWhenI 🇻🇦 584 299 135ms 20 Jun 2024 345th KatieLG 🇬🇧 582 123 39ms 2 Oct 2025 346th prplz 🇦🇺 582 164 12ms 1 Nov 2023 346th bricknellj 582 164 14ms 1 Dec 2023 348th snoozingnewt 🇨🇦 577 185 1,209ms 18 Oct 2025 349th Shanethegamer 🇺🇸 575 156 498ms 16 Jan 2024 350th Shanethegamer 🇺🇸 575 166 14ms 1 Nov 2023 351st dokutan 572 167 14ms 5 Jul 2024 351st blaztoma 🇱🇹 572 167 11ms 10 Jan 2026 353rd two-bad 🇬🇧 571 172 10ms 25 Feb 2024 354th alexsave 568 173 10ms 13 Nov 2025 355th bac0id 568 297 445ms 8 Jan 2025 356th tigerdan2 🇩🇪 568 332 480ms 30 Nov 2025 357th janbehrens 🇩🇪 565 169 13ms 30 Nov 2023 358th AlephSquirrel 560 268 13ms 21 Oct 2024 359th blaztoma 🇱🇹 559 151 4ms 12 Jan 2026 360th MeWhenI 🇻🇦 559 257 69ms 6 Nov 2023 361st guilhem-roy 🇫🇷 555 172 11ms 29 May 2025 362nd tomh1012 551 259 488ms 21 days ago 363rd dokutan 550 163 411ms 5 Jul 2024 364th KasperKivimaeki 🇫🇮 549 174 30ms 1 Dec 2025 365th emgordon154 546 131 39ms 23 Nov 2024 366th bac0id 544 274 2ms 8 Jan 2025 367th hellwue 543 176 11ms 9 Nov 2023 368th ahmetdemirag 🇨🇾 540 177 12ms 20 Jun 2024 368th andrewjc2000 540 177 11ms 16 Jan 2026 370th janAkali 🇷🇺 538 268 419ms 7 Jun 2025 371st Alex-x90 🇺🇸 537 178 14ms 6 Nov 2023 371st Yewzir 🇧🇪 537 178 12ms 9 Dec 2025 373rd Shanethegamer 🇺🇸 537 210 3ms 1 Nov 2023 374th inventshah 534 179 11ms 3 Dec 2023 374th solisolu 534 179 14ms 2 days ago 376th cros107 🇦🇺 531 180 11ms 2 Nov 2023 377th CaedenHarper 🇨🇦 526 391 301ms 2 Nov 2025 378th Shanethegamer 🇺🇸 519 227 4ms 1 Nov 2023 379th KatieLG 🇬🇧 516 207 1,204ms 15 Oct 2024 380th Aurel300 🇨🇭 515 405 279ms 21 Jun 2024 381st commandz0 🇺🇸 513 186 13ms 6 Nov 2023 382nd commandz0 🇺🇸 512 175 510ms 1 Sep 2025 383rd Emutis 🇱🇹 511 187 13ms 12 Oct 2025 384th MeWhenI 🇻🇦 510 221 13ms 20 Jun 2024 385th snoozingnewt 🇨🇦 508 240 19ms 18 Oct 2025 386th snoozingnewt 🇨🇦 507 174 339ms 27 Nov 2025 387th albanian-laundromat 505 223 7ms 2 Jul 2025 388th snoozingnewt 🇨🇦 504 374 406ms 18 Oct 2025 389th lelbal 500 191 11ms 12 Nov 2025 390th BambooleanLogic 🇸🇪 498 197 10ms 1 Nov 2023 391st adamnielson42 🇺🇸 497 192 12ms 1 Nov 2023 392nd AlephSquirrel 495 360 6ms 14 May 2025 393rd snoozingnewt 🇨🇦 494 194 1,242ms 18 Oct 2025 394th Shanethegamer 🇺🇸 494 304 47ms 30 Aug 2024 395th MateuszPietrzak 🇵🇱 490 344 67ms 19 Nov 2023 396th bpharaldsson 487 196 12ms 13 Feb 2026 397th klixel 🇨🇦 485 197 11ms 19 Jul 2025 397th Babafaba 485 197 14ms 17 Nov 2025 397th vhoulbreque 🇫🇷 485 197 11ms 26 Nov 2025 400th Bmrl7 482 198 12ms 23 Nov 2025 First Prev 321–400 of 520 Next Last