The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 4 days. Why not try and solve them ahead of time?
Forsyth–Edwards Notation 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 721st Yewzir 🇧🇪 464 228 427ms 11 Feb 2024 722nd Jacob-Gendelman 463 247 10ms 27 Jul 2023 722nd epic-programmer-guy 463 247 10ms 1 Jan 2024 724th dokutan 462 277 2ms 16 Jul 2024 725th KatieLG 🇬🇧 453 187 1,247ms 1 May 2023 726th dokutan 447 360 42ms 25 Aug 2024 727th jtaxen 445 257 9ms 26 Apr 2024 728th The-Wolfson 442 312 144ms 9 Feb 2025 729th TheZwierzLF 🇵🇱 441 155 37ms 21 Dec 2025 730th xPMo 441 222 3ms 28 Jun 2024 731st MassimoParisi 441 259 11ms 20 Sep 2024 732nd snoozingnewt 🇨🇦 438 147 163ms 31 Oct 2025 733rd ridingqwerty 🇺🇸 436 222 556ms 22 Jan 2024 734th cmccandless 435 263 10ms 16 Oct 2023 735th stephanie-flower 431 259 10ms 2 Nov 2025 736th bac0id 431 280 469ms 11 Jan 2025 737th dokutan 428 394 1ms 6 Dec 2024 738th Solathian 425 146 5ms 38 hours ago 739th puffertron 423 270 10ms 10 Jan 2024 739th ComputerKWasTaken 🇺🇸 423 270 10ms 21 Jan 2025 741st OCNeve 422 271 10ms 18 Jun 2024 742nd apokryfos 421 265 9ms 20 Aug 2023 743rd KatieLG 🇬🇧 420 163 32ms 29 Aug 2024 744th Maashau 419 240 2ms 15 Dec 2025 745th MamoonUddin 416 275 10ms 3 Dec 2024 746th epic-programmer-guy 416 318 136ms 15 Apr 2024 747th JOrE20 415 399 59ms 15 Feb 2026 748th jalbertgordon 411 278 10ms 23 Oct 2023 749th SirFireball3521 410 157 165ms 26 Feb 2024 750th dokutan 409 273 10ms 29 Mar 2025 751st cingulataluke 407 281 10ms 27 Aug 2023 752nd KatieLG 🇬🇧 405 335 450ms 19 Oct 2024 753rd Widgitty 404 249 2ms 23 Sep 2025 754th dylanjones92 396 289 10ms 17 Jan 2024 754th alfonsoalves 396 289 10ms 26 Feb 2024 756th MeWhenI 🇻🇦 395 324 4ms 13 Dec 2023 757th alecdavidson 394 290 15ms 9 Jun 2023 758th bac0id 389 259 2ms 11 Jan 2025 759th MyXoToD 🇩🇪 389 287 9ms 1 Jul 2024 760th fischfood 388 277 5ms 15 Aug 2024 761st yuchuehw 385 352 481ms 3 Jan 2024 762nd dokutan 385 708 12ms 28 Jun 2025 763rd zt14427 382 299 10ms 11 Feb 2025 764th Bananapants22 376 304 10ms 13 May 2023 765th dokutan 374 342 3ms 7 Dec 2024 766th MeWhenI 🇻🇦 372 436 2ms 1 May 2023 767th TimSvensson 371 308 10ms 5 Nov 2023 768th Yewzir 🇧🇪 370 234 815ms 5 Apr 2024 769th dokutan 366 286 1,023ms 5 Feb 2025 770th MeWhenI 🇻🇦 365 454 63ms 1 May 2023 771st KatieLG 🇬🇧 364 216 4ms 1 May 2023 772nd MeWhenI 🇻🇦 357 486 305ms 1 May 2023 773rd liviucerchez 352 306 5ms 14 Oct 2023 774th dokutan 352 336 89ms 26 Jan 2026 775th dokutan 352 461 2ms 29 Jun 2025 776th Creator-land 349 328 10ms 10 Jan 2024 777th KatieLG 🇬🇧 347 305 394ms 19 Oct 2024 778th dokutan 343 381 406ms 23 Sep 2024 779th dokutan 341 508 275ms 19 Oct 2024 780th Zhenyu-Bo 338 338 10ms 31 Jul 2025 780th DrakeSeteraO 338 338 10ms 12 Nov 2025 782nd lynn 337 339 9ms 14 Oct 2023 783rd Bit125 336 340 10ms 31 Jan 2024 784th dokutan 335 258 561ms 7 Mar 2024 785th Blockyheadman 335 360 72ms 5 Nov 2025 786th dokutan 325 369 65ms 12 Mar 2025 787th mrmena 🇦🇺 325 399 41ms 16 Apr 2024 788th dokutan 317 381 467ms 8 Nov 2025 789th MeWhenI 🇻🇦 315 311 2ms 18 Nov 2023 790th MeWhenI 🇻🇦 311 385 538ms 1 Nov 2023 791st MeWhenI 🇻🇦 310 381 76ms 1 May 2023 792nd aksyristos 304 225 39ms 28 Oct 2024 793rd MeWhenI 🇻🇦 304 435 152ms 1 May 2023 794th dokutan 301 487 1,357ms 14 Oct 2024 795th bwat2 295 460 412ms 11 May 2023 796th Weston49 292 382 10ms 20 Oct 2023 797th dokutan 291 458 1ms 26 Jul 2024 798th sojumasterGA 288 265 274ms 2 May 2023 799th dokutan 284 477 382ms 24 Sep 2025 800th dokutan 282 357 2ms 8 Nov 2025 First Prev 721–800 of 858 Next Last