The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 26 hours. Why not try and solve them ahead of time?
Morse Decoder 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 olivermrose 🇺🇸 545 120 37ms 28 Oct 2021 322nd helbling 🇨🇭 545 178 13ms 14 Sep 2024 323rd error256 544 160 81ms 24 May 2025 324th evan-schiewe 544 251 466ms 21 Nov 2021 325th Natanaelel 🇸🇪 543 169 1,485ms 22 Jan 2023 326th CaedenHarper 🇨🇦 542 164 10ms 1 Aug 2025 327th Natanaelel 🇸🇪 542 179 11ms 22 Jan 2023 328th dokutan 542 230 425ms 9 Nov 2025 329th dokutan 541 188 3,231ms 8 Sep 2025 330th janbehrens 🇩🇪 541 252 425ms 10 Jan 2022 331st GrayJoKing 🇦🇺 540 474 2ms 14 Nov 2020 332nd adamnielson42 🇺🇸 539 165 10ms 26 May 2023 333rd user189032 539 180 12ms 29 May 2019 333rd itsh01 539 180 11ms 12 May 2022 333rd dokutan 539 180 10ms 8 Sep 2025 336th AlexDaniel 🇪🇪 536 121 148ms 13 Mar 2018 337th AlephSquirrel 536 166 15ms 13 Aug 2023 338th janbehrens 🇩🇪 536 239 1ms 21 Mar 2022 339th emgordon154 534 463 2ms 9 Jun 2025 340th snoozingnewt 🇨🇦 533 309 3ms 9 Nov 2025 341st BambooleanLogic 🇸🇪 530 183 11ms 5 Jul 2023 342nd alexkunin 528 184 10ms 6 Jul 2019 343rd MeWhenI 🇻🇦 522 142 419ms 14 Feb 2023 344th Natanaelel 🇸🇪 520 343 131ms 22 Jan 2023 345th AlephSquirrel 519 165 486ms 21 Jan 2024 346th coreynash 519 187 11ms 25 May 2023 347th IISResetMe 517 165 309ms 2 Dec 2025 348th Bulmenisaurus 517 172 10ms 30 Jul 2024 349th blaztoma 🇱🇹 517 266 150ms 1 Dec 2025 350th lacroixjonathan87 515 202 4ms 3 Jan 2021 351st ShiraJoseph 🇺🇸 514 189 13ms 28 Apr 2022 352nd inventshah 512 167 548ms 16 Jan 2024 353rd Natanaelel 🇸🇪 511 127 177ms 6 hours ago 354th unfinishedprogram 511 190 12ms 14 Jul 2023 355th lynn 510 102 40ms 19 Oct 2023 356th dokutan 510 240 2ms 21 Apr 2024 357th filharmonista 510 251 2ms 9 Mar 2020 358th inventshah 508 175 10ms 18 Jan 2023 359th moikaturns 🇬🇧 508 191 10ms 10 Nov 2022 360th tatzyr 🇯🇵 507 129 35ms 25 Mar 2025 361st gnlow 🇰🇷 506 192 10ms 18 Feb 2021 362nd JDiLenarda 🇫🇷 506 301 1,399ms 29 Nov 2023 363rd marcin7Cd 503 177 15ms 14 Mar 2020 364th eranws 503 193 11ms 1 Nov 2022 365th billings7 🇬🇧 502 272 375ms 19 May 2024 366th Natanaelel 🇸🇪 499 131 47ms 9 Jun 2023 367th MeWhenI 🇻🇦 499 330 2ms 10 Sep 2022 368th janbehrens 🇩🇪 498 195 11ms 17 Jun 2023 369th jwhear 🇺🇸 497 500 1,752ms 30 Sep 2024 370th alexsave 495 196 10ms 14 Dec 2025 371st tobeannouncd 494 361 123ms 8 Jan 2024 372nd h3ra993huskp 🇯🇵 493 253 675ms 30 Nov 2025 373rd marcin7Cd 493 519 6ms 16 Nov 2020 374th gastropner 492 260 2ms 24 Dec 2020 375th m-tkach 🇺🇦 491 181 10ms 31 Dec 2022 376th MeWhenI 🇻🇦 490 232 144ms 27 Jan 2023 377th janbehrens 🇩🇪 488 272 3,200ms 20 Nov 2022 378th BREMAUCY 🇫🇷 486 183 10ms 24 Jul 2025 379th GrayJoKing 🇦🇺 484 180 95ms 10 Aug 2023 380th emgordon154 482 211 3,406ms 3 Nov 2024 381st janbehrens 🇩🇪 481 216 5ms 2 Jul 2023 382nd janbehrens 🇩🇪 480 261 588ms 24 Mar 2022 383rd dokutan 479 182 83ms 26 Jan 2026 384th davitf 478 186 10ms 30 Oct 2018 385th Kibble 478 203 10ms 27 Jul 2020 386th madex 🇩🇪 477 213 3,150ms 24 hours ago 387th scpchicken 🇵🇼 473 128 4ms 24 Feb 2023 388th emgordon154 472 305 4ms 26 Jan 2025 389th Ripick 471 355 374ms 11 Aug 2024 390th elisherer 🇮🇱 469 207 11ms 18 Apr 2019 390th weliveinhell 🇭🇹 469 207 11ms 1 Feb 2024 390th JOrE20 469 207 10ms 4 Feb 2026 393rd bluebear94 467 139 158ms 2 Mar 2018 394th hiddicop 🇸🇪 467 140 35ms 31 Jan 2021 395th MeWhenI 🇻🇦 467 187 180ms 3 Aug 2024 396th madeforlosers 467 208 13ms 7 hours ago 397th dokutan 466 159 585ms 8 Sep 2025 398th AlephSquirrel 464 112 38ms 28 Dec 2023 399th KatieLG 🇬🇧 464 141 432ms 26 May 2021 400th dokutan 463 345 2ms 8 Feb 2026 First Prev 321–400 of 899 Next Last