The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 2 days. Why not try and solve them ahead of time?
12 Days of Christmas 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 481st revlayle 🇺🇸 866 480 374ms 31 May 2022 482nd user189032 866 499 124ms 29 May 2019 483rd inventshah 866 508 61ms 16 Sep 2023 484th KatieLG 🇬🇧 866 528 2ms 6 Mar 2021 485th kusune 🇯🇵 865 412 2ms 29 Sep 2023 486th AnAwesomGuy 865 462 1,263ms 17 Sep 2025 487th didion0 🇺🇸 865 464 9ms 8 Jan 2021 487th CatsAreFluffy 865 464 10ms 18 Dec 2022 487th iliazeus 865 464 10ms 10 Mar 2023 487th owen-c-parker 🇺🇸 865 464 12ms 29 Mar 2023 487th crammond 865 464 9ms 14 Aug 2023 487th Maznek 865 464 11ms 27 Dec 2023 487th thadeucity 865 464 11ms 23 May 2025 487th alexsave 865 464 11ms 16 Sep 2025 495th sean-niemann 🇺🇸 865 469 576ms 11 Nov 2025 496th dokutan 865 492 2ms 30 Nov 2025 497th MeWhenI 🇻🇦 865 522 212ms 13 Nov 2022 497th vidanm 🇫🇷 865 522 196ms 11 Jun 2025 499th MeWhenI 🇻🇦 865 531 40ms 3 Jul 2023 500th GolfingSuccess 🇬🇷 864 370 10ms 11 Mar 2025 501st SephQ 864 440 34ms 31 Dec 2020 501st JRaspass 🇬🇧 864 440 36ms 18 Jan 2023 503rd MeWhenI 🇻🇦 864 444 157ms 3 Aug 2024 504th inventshah 864 473 2ms 19 Aug 2023 505th tomh1012 864 481 421ms 3 Dec 2025 506th sean-niemann 🇺🇸 864 482 1ms 16 Jan 2022 507th yzhs 🇩🇪 864 500 123ms 24 Jul 2021 508th nwellnhof 🇩🇪 864 509 62ms 9 Jan 2022 509th GinjaNinja32 864 523 210ms 16 Apr 2020 510th primo-ppcg 🇹🇭 863 413 2ms 9 Nov 2021 511th BlankSpruce 863 450 10ms 27 Aug 2024 512th thantos 863 465 13ms 21 Feb 2018 512th m1el 863 465 10ms 28 Aug 2020 512th CaedenHarper 🇨🇦 863 465 10ms 6 Sep 2025 515th Shanethegamer 🇺🇸 863 473 2,585ms 31 Oct 2024 516th Attero 🇸🇪 863 519 446ms 1 May 2020 517th JesperJ 862 452 258ms 9 Jun 2020 517th rvdnieuwendijk 🇳🇱 862 452 283ms 23 Oct 2020 517th IISResetMe 862 452 262ms 21 Dec 2025 520th Attero 🇸🇪 862 459 5ms 25 Sep 2023 521st Giga-Bowser 862 466 11ms 4 Jan 2022 521st draem 862 466 11ms 31 Jul 2024 521st c-py 862 466 9ms 1 Nov 2025 521st tomh1012 862 466 10ms 3 Dec 2025 521st egertaia 862 466 10ms 9 Jan 2026 526th jws305 862 482 381ms 21 Nov 2021 526th RainOrigami 🇩🇪 862 482 382ms 21 Dec 2021 528th speles 🇺🇦 862 483 1ms 29 Oct 2023 529th albanian-laundromat 862 522 293ms 4 Dec 2025 530th dokutan 862 546 76ms 22 hours ago 531st kg583 🇺🇸 861 450 492ms 5 Feb 2026 532nd CaedenHarper 🇨🇦 861 464 967ms 6 Sep 2025 533rd sean-niemann 🇺🇸 861 495 1ms 14 Jul 2025 534th janAkali 🇷🇺 861 500 127ms 7 Oct 2024 535th strout 861 502 121ms 15 Aug 2022 536th MWI-polygolf 861 503 105ms 6 Dec 2023 537th sean-niemann 🇺🇸 861 511 56ms 17 Jan 2022 538th GrayJoKing 🇦🇺 860 404 128ms 8 Dec 2020 539th SubsTheTechnomancer 860 442 35ms 3 Mar 2023 539th snoozingnewt 🇨🇦 860 442 34ms 23 Sep 2023 541st Natanaelel 🇸🇪 860 467 9ms 11 Sep 2021 541st SirBogman 🇺🇸 860 467 10ms 10 Dec 2021 541st GeorgeStechman 🇬🇧 860 467 10ms 20 Sep 2022 541st DayDun 🇸🇪 860 467 9ms 19 Jan 2023 541st strattonwhisler 860 467 10ms 27 Mar 2025 541st Andrey-Plotnikov 860 467 10ms 27 Jun 2025 541st Yax42 🇫🇷 860 467 10ms 13 Feb 2026 548th Shanethegamer 🇺🇸 860 469 160ms 28 Jul 2021 549th Shanethegamer 🇺🇸 860 472 530ms 31 Oct 2024 550th MeWhenI 🇻🇦 860 475 2,925ms 24 Oct 2024 551st jahakari 860 483 389ms 21 Nov 2021 551st SmartK8 🇨🇿 860 483 423ms 30 Oct 2022 551st DialFrost 🇸🇬 860 483 82ms 19 Feb 2025 554th Shanethegamer 🇺🇸 860 525 183ms 11 Dec 2022 555th iznax 859 484 389ms 21 Nov 2021 555th leth4 859 484 375ms 5 Jul 2023 557th CaedenHarper 🇨🇦 859 521 485ms 10 Oct 2025 558th msbranicky 859 526 199ms 6 Oct 2023 558th dokutan 859 526 130ms 17 Oct 2024 560th KatieLG 🇬🇧 858 451 1,271ms 29 Aug 2024 First Prev 481–560 of 4,083 Next Last