The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 6 days. Why not try and solve them ahead of time?
Factorial Factorisation 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 641st Code-Coder-coder 468 178 35ms 23 Nov 2025 642nd msbranicky 466 167 21ms 18 Apr 2024 643rd msbranicky 465 167 1,188ms 16 Apr 2024 644th msbranicky 465 172 10ms 21 Apr 2024 645th KatieLG 🇬🇧 465 179 17ms 13 Apr 2024 646th Bodo171 462 180 31ms 30 Dec 2024 647th TheZwierzLF 🇵🇱 461 173 515ms 20 Dec 2025 648th resoNathan 460 181 39ms 25 Apr 2024 649th Natanaelel 🇸🇪 457 87 19ms 16 Apr 2024 650th adamnielson42 🇺🇸 455 183 24ms 23 Apr 2024 651st blaztoma 🇱🇹 454 160 293ms 12 Oct 2025 652nd SURAJMITTAL 452 184 33ms 20 Dec 2024 653rd yasna-nsh 450 185 25ms 7 Oct 2025 654th ei14 447 186 54ms 8 May 2024 655th dokutan 446 163 316ms 20 Jun 2024 656th KatieLG 🇬🇧 445 179 651ms 13 Apr 2024 657th Stockoh 🇫🇷 445 187 12ms 26 Apr 2024 658th msbranicky 444 245 414ms 21 Apr 2024 659th XioR112 🇵🇱 440 189 34ms 3 Jun 2024 660th Alex-Huggett 🇬🇧 438 190 27ms 14 Apr 2024 661st kasarino 437 236 43ms 3 Feb 2026 662nd wh3n3v3r 🇨🇿 436 191 28ms 14 Nov 2024 662nd Troon 436 191 23ms 6 Dec 2024 664th msbranicky 434 158 46ms 16 Apr 2024 665th gallium-gonzollium 433 192 39ms 26 Aug 2024 665th ItsEthanDev 433 192 34ms 16 Nov 2024 665th croc54 433 192 21ms 30 Dec 2024 665th kadamkaustubh 433 192 19ms 3 Oct 2025 669th codewrite 🇬🇧 431 193 17ms 11 Jun 2025 670th Ripick 430 270 369ms 15 Aug 2024 671st Mabeloid 🇳🇴 425 196 19ms 23 Sep 2024 672nd msbranicky 423 237 2,650ms 18 Apr 2024 673rd corbob 🇨🇦 422 193 309ms 3 May 2024 674th NerdyMcNerd42 416 200 44ms 20 Feb 2025 675th kasarino 414 205 2ms 3 Feb 2026 676th wobblybits 412 202 16ms 24 Aug 2025 677th Yewzir 🇧🇪 411 464 1,729ms 5 Jun 2024 678th msbranicky 410 178 23ms 16 Apr 2024 679th adoxography 410 203 21ms 27 Apr 2024 680th madex 🇩🇪 409 221 68ms 4 days ago 681st Andrey2001 408 204 26ms 1 Feb 2026 682nd KatieLG 🇬🇧 408 1,124 1ms 13 Apr 2024 683rd JunkIce 406 205 16ms 3 Dec 2024 684th ei14 406 247 1,994ms 8 May 2024 685th Mabeloid 🇳🇴 404 197 755ms 17 Sep 2024 685th JunkIce 404 197 496ms 8 Jan 2025 687th aalec 404 206 17ms 23 Apr 2024 688th snoozingnewt 🇨🇦 401 248 428ms 9 Oct 2025 689th a6166231 🇨🇳 400 200 11ms 15 May 2025 690th msbranicky 391 186 185ms 14 Apr 2024 691st RaBa21 🇭🇺 391 213 55ms 19 Jul 2025 692nd JPRuskin 🇬🇧 390 209 714ms 25 Apr 2024 693rd Languag3 387 215 13ms 10 Oct 2024 694th tomh1012 387 257 492ms 4 Dec 2025 695th saito-ta 🇯🇵 379 1,211 1ms 25 Apr 2024 696th tomh1012 376 213 25ms 5 days ago 697th rollsroyce0 372 224 746ms 11 Sep 2024 698th kmathis22 372 243 62ms 23 Dec 2025 699th aksyristos 370 225 16ms 5 Nov 2024 700th kitotch 369 230 2ms 4 days ago 701st TRexOnGit 367 218 20ms 22 Jul 2025 702nd FortuiteMan 🇫🇷 367 227 12ms 16 Oct 2024 703rd sciencejiho 363 229 20ms 26 Apr 2024 703rd julian-hoelz 363 229 14ms 22 Sep 2024 703rd tomh1012 363 229 37ms 22 days ago 706th mdnestor 360 231 59ms 2 Jul 2024 707th msbranicky 359 180 184ms 16 Apr 2024 708th gnuvince 355 112 24ms 29 Jun 2025 709th nstearns96 🇬🇧 353 236 2,249ms 21 Jan 2025 710th msbranicky 353 300 1,225ms 14 Jan 2025 711th kitotch 351 228 11ms 4 days ago 712th kevinnaviapaiva 345 321 142ms 6 Mar 2025 713th yzhs 🇩🇪 341 244 23ms 17 Jan 2025 714th madeforlosers 338 237 11ms 5 Dec 2024 715th noahdorsch 329 325 1,491ms 27 Dec 2025 716th Andrey2001 328 243 634ms 26 Nov 2025 717th cthierfelder 🇲🇨 325 256 51ms 8 Sep 2025 718th vhoulbreque 🇫🇷 324 257 37ms 11 Feb 2025 719th ComputerKWasTaken 🇺🇸 323 258 9ms 1 Jul 2024 720th Alex-Huggett 🇬🇧 323 308 429ms 14 Apr 2024 First Prev 641–720 of 1,484 Next Last