The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 34 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 401st SirBogman 🇺🇸 460 186 547ms 23 Jul 2025 402nd voytxt 🇨🇿 458 212 13ms 20 Feb 2025 403rd aksyristos 456 195 10ms 3 days ago 404th yzhs 🇩🇪 456 391 128ms 2 Aug 2021 405th iznax 455 300 506ms 21 Nov 2021 406th prestosilver 🇺🇸 455 367 366ms 4 days ago 407th elgan65536 🇺🇸 452 396 199ms 6 Mar 2024 408th bwat2 450 277 625ms 8 Mar 2022 409th dzhang314 449 198 10ms 14 Aug 2019 409th StefanHabel 🇨🇦 449 198 11ms 11 Dec 2022 409th KatieLG 🇬🇧 449 198 10ms 15 Sep 2025 412th olleicua 🇺🇸 448 146 34ms 25 Mar 2025 413th cbondurant 447 199 17ms 10 May 2021 414th kistlerf 🇨🇭 445 200 10ms 19 May 2025 414th qpwoeirut 445 200 16ms 29 Aug 2025 416th ahmetdemirag 🇨🇾 443 201 10ms 18 Nov 2024 417th emgordon154 443 226 8ms 13 Dec 2024 418th dokutan 439 199 168ms 8 Sep 2025 419th Natanaelel 🇸🇪 436 204 15ms 20 Jan 2023 420th quimey 434 205 10ms 17 Jul 2023 420th madex 🇩🇪 434 205 10ms 15 hours ago 422nd nullshallot 433 197 291ms 7 Jan 2025 423rd KatieLG 🇬🇧 432 198 403ms 6 Oct 2025 424th guilhem-roy 🇫🇷 430 207 10ms 25 Feb 2022 424th RDShah 430 207 10ms 16 Jan 2023 424th Pyroan 430 207 10ms 2 Mar 2025 427th jared-hughes 427 153 39ms 11 Dec 2022 428th janAkali 🇷🇺 427 391 415ms 2 Jun 2025 429th janbehrens 🇩🇪 426 209 10ms 17 Jun 2023 430th lynn 424 143 3ms 20 Apr 2021 431st za3k 424 210 10ms 13 Oct 2022 431st Babafaba 424 210 12ms 23 Nov 2025 433rd c0d3-4-F00d 🇩🇪 424 302 2ms 11 Feb 2022 434th nullie 422 211 10ms 9 Jun 2022 435th kaascevich 422 367 1,033ms 14 Sep 2025 436th arctouch-cristiannevianna 421 324 380ms 1 Mar 2024 437th janbehrens 🇩🇪 420 297 617ms 7 Jan 2021 438th commandz0 🇺🇸 418 213 15ms 6 Apr 2023 439th viv511 417 318 1,525ms 16 Feb 2025 440th The3gs 416 214 10ms 13 Oct 2020 440th RaBa21 🇭🇺 416 214 17ms 18 Jul 2025 442nd sambirnbaum1 414 215 20ms 13 Oct 2019 442nd cros107 🇦🇺 414 215 17ms 10 Sep 2025 442nd Lv0Sys 🇵🇱 414 215 10ms 30 Nov 2025 445th dokutan 414 354 99ms 4 Feb 2025 446th MeWhenI 🇻🇦 412 147 3ms 16 Apr 2023 447th Mabeloid 🇳🇴 412 216 10ms 12 Sep 2024 448th hoodadam 410 217 9ms 11 Jun 2019 448th abailey2020 🇺🇸 410 217 10ms 19 Aug 2020 448th CedricGebistorf 410 217 9ms 20 Feb 2022 448th SB-945 410 217 11ms 10 Mar 2024 452nd Babafaba 407 210 457ms 23 Nov 2025 453rd Troon 406 219 16ms 21 Oct 2022 454th andrewjc2000 404 220 10ms 16 Jul 2025 455th janbehrens 🇩🇪 403 184 580ms 11 Jul 2023 456th hyvyys 403 241 11ms 18 Sep 2020 457th Schmitt-Very-Cool 402 310 641ms 3 Oct 2025 458th Starwort 🇬🇧 401 222 12ms 10 Feb 2020 459th Natanaelel 🇸🇪 398 152 5ms 12 Feb 2023 460th madex 🇩🇪 396 165 35ms 15 hours ago 461st Lv0Sys 🇵🇱 396 187 659ms 30 Nov 2025 462nd Mabeloid 🇳🇴 396 216 610ms 17 Sep 2024 463rd pyrolitic 🇮🇪 395 225 11ms 6 Apr 2022 464th alangodfrey 394 226 10ms 31 Jan 2019 465th Yewzir 🇧🇪 394 405 2ms 18 Oct 2023 466th knutae 🇳🇴 392 227 11ms 21 Aug 2021 467th hamhub7 392 348 467ms 18 Aug 2022 468th blaztoma 🇱🇹 391 155 3ms 22 Oct 2025 469th vezzick 390 228 10ms 6 Mar 2021 470th didion0 🇺🇸 390 249 11ms 1 Dec 2021 471st kevinmchung 388 229 11ms 24 Feb 2018 472nd jerrandolph 388 472 317ms 21 Apr 2020 473rd Lv0Sys 🇵🇱 387 169 35ms 30 Nov 2025 474th msrawson 387 230 10ms 2 Sep 2018 474th ydevor 🇮🇱 387 230 10ms 16 Feb 2021 476th ArmaanAS 387 251 11ms 25 Mar 2021 477th lukechampine 386 474 320ms 19 Apr 2020 478th ToriTheChicken 384 253 11ms 2 Aug 2020 479th bastienvoirin 🇫🇷 383 232 10ms 5 Apr 2020 480th jameswmccarty 382 233 10ms 7 Mar 2025 First Prev 401–480 of 899 Next Last