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 798th TannerJ07 🇺🇸 833 542 140ms 6 Apr 2025 802nd sean-niemann 🇺🇸 832 430 2ms 3 Jan 2024 802nd neel11235813 832 430 2ms 26 Mar 2024 804th CatsAreFluffy 832 466 418ms 15 Jan 2024 805th SteveHales 832 499 81ms 15 Oct 2025 806th lynn 832 528 14ms 17 Nov 2021 807th b97tsk 832 541 282ms 27 Apr 2020 808th Creative0708 🇨🇦 832 543 125ms 16 Dec 2023 809th robymus 831 457 38ms 18 Sep 2018 809th jbbarth 🇫🇷 831 457 33ms 23 Aug 2021 809th dokutan 831 457 34ms 21 Apr 2025 812th gjh71 🇳🇱 831 469 275ms 25 Dec 2020 813th itsh01 831 483 10ms 16 Mar 2022 813th predyy 831 483 10ms 29 Jun 2022 813th lewdev 🇺🇸 831 483 11ms 12 Feb 2023 813th SiddharthShyniben 831 483 10ms 1 Dec 2024 817th msbranicky 831 492 2ms 20 Jan 2025 818th MiffOttah 831 500 407ms 21 Nov 2021 818th dpethes 831 500 392ms 10 Jan 2024 820th Hillsoft 831 520 123ms 31 Jul 2022 821st MeWhenI 🇻🇦 831 529 16ms 18 Nov 2021 822nd chartung17 831 539 426ms 1 Jan 2024 823rd atsushiootani 830 458 36ms 27 Aug 2018 823rd vincecoss 830 458 38ms 15 May 2022 823rd paul-c-hartman 830 458 35ms 7 Mar 2025 826th commandz0 🇺🇸 830 467 500ms 15 Jan 2024 826th dokutan 830 467 359ms 8 Feb 2026 828th DialFrost 🇸🇬 830 477 5ms 30 Nov 2023 829th msbranicky 830 492 2,719ms 11 Jan 2025 830th gdyr 830 544 224ms 3 Mar 2023 831st matiasbontempo 829 484 10ms 9 Sep 2022 831st Quadruplay 829 484 9ms 20 Dec 2024 833rd albanian-laundromat 829 499 113ms 11 Nov 2025 834th malworthy 829 501 395ms 24 Oct 2023 834th arcpolaris 829 501 425ms 27 Mar 2025 836th xiaoyiming123 829 502 2ms 11 Aug 2025 837th deltaphc 829 519 130ms 19 Jan 2020 838th jerrandolph 829 543 315ms 21 Oct 2023 839th LostSyntax21 🇬🇧 828 459 35ms 5 Jul 2025 840th gunnermanx 828 485 11ms 25 Jan 2019 840th chloeching-amino 828 485 10ms 24 May 2020 840th revlayle 🇺🇸 828 485 10ms 16 Feb 2021 840th CubeyTheCube 828 485 10ms 9 Aug 2022 840th johnkiernander 828 485 10ms 10 Dec 2025 840th Nemikolh 🇫🇷 828 485 10ms 23 Dec 2025 846th JonMartinTx 828 502 374ms 26 Apr 2024 846th najs91 828 502 413ms 8 Oct 2024 846th amazingalek 🇳🇴 828 502 421ms 21 Jan 2026 849th warmCabin 828 515 1ms 11 Nov 2019 849th micrx 828 515 1ms 6 Feb 2021 849th heromk 828 515 1ms 15 Jul 2021 849th aDwarfNamedUrist 828 515 1ms 8 Nov 2022 849th FlyingPenguin223 828 515 2ms 25 Dec 2024 849th NickTheEASDude 🇺🇸 828 515 1ms 28 Dec 2024 855th msbranicky 828 520 132ms 5 Sep 2023 856th msbranicky 828 544 304ms 31 Aug 2023 857th alexhuntley 827 372 6ms 11 Apr 2021 858th inventshah 827 469 1ms 5 Nov 2022 859th joshinryz 827 471 259ms 3 Jun 2020 859th ScriptingPro 827 471 261ms 20 Nov 2020 861st jkelly467 827 494 2,518ms 28 Dec 2025 862nd fraserli 🇦🇺 827 546 154ms 2 Jan 2022 863rd jacobly0 🇺🇸 827 606 1,670ms 18 Sep 2025 864th Waffle3z 826 460 39ms 21 Jan 2021 864th aksyristos 826 460 35ms 31 Jan 2023 866th PlatoHero 826 472 270ms 26 Jan 2024 866th SigitasG 826 472 246ms 13 Jun 2025 868th fitzdotlol 🇺🇸 826 486 11ms 20 Mar 2022 868th Larento 826 486 9ms 14 Oct 2023 870th Yewzir 🇧🇪 826 489 3ms 14 May 2023 871st byronknoll 🇺🇸 826 504 1ms 21 Jan 2024 872nd GalladeGuy 🇺🇸 826 516 1ms 13 Apr 2019 872nd JRaspass 🇬🇧 826 516 1ms 28 Dec 2021 872nd dokutan 826 516 1ms 10 Apr 2025 875th byronknoll 🇺🇸 826 533 466ms 21 Jan 2024 876th MJKWoolnough 826 545 283ms 10 Aug 2022 877th ivan-pi 🇸🇮 826 556 38ms 23 Apr 2020 878th janbehrens 🇩🇪 825 492 559ms 24 Apr 2023 879th derekmc 825 495 2,652ms 25 Nov 2024 880th Shnapster 825 504 401ms 23 Sep 2023 First Prev 801–880 of 4,083 Next Last