The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 25 hours. 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 881st janbehrens 🇩🇪 825 492 559ms 24 Apr 2023 882nd derekmc 825 495 2,652ms 25 Nov 2024 883rd Shnapster 825 504 401ms 23 Sep 2023 884th SubsTheTechnomancer 824 434 2ms 10 Mar 2023 884th snoozingnewt 🇨🇦 824 434 2ms 23 Sep 2023 886th oising 824 473 292ms 3 Jun 2020 886th jdallma 824 473 266ms 3 Jun 2020 888th NatNgs 824 487 9ms 8 Jan 2020 888th KaeruCT 824 487 9ms 2 Dec 2020 888th mcculloughjchris 824 487 10ms 31 Oct 2022 888th madex 🇩🇪 824 487 9ms 19 Dec 2024 892nd tsunderu 🇯🇵 824 505 2ms 1 Sep 2021 893rd EnigmaticError 824 517 1ms 26 Jan 2024 893rd HumanoidCPU 824 517 1ms 14 Mar 2024 895th tcql 🇺🇸 824 522 300ms 21 Apr 2024 896th JRaspass 🇬🇧 823 422 130ms 5 Dec 2022 897th ocefra 823 481 4ms 6 Jan 2025 898th dzshn 823 488 9ms 14 Apr 2021 898th vlad-ushakov 823 488 10ms 22 Mar 2023 900th emgordon154 823 496 2,549ms 25 days ago 901st gastropner 823 506 2ms 5 Jul 2025 902nd logancammish2 823 518 1ms 6 Feb 2021 902nd mtirado1 823 518 1ms 14 Aug 2022 902nd Phil-RGOMEGA 823 518 2ms 5 May 2023 905th neihousaigaai 823 544 430ms 27 Dec 2021 906th okaponta 823 549 146ms 13 Jan 2024 907th msbranicky 822 503 115ms 28 Aug 2023 907th arctouch-cristiannevianna 822 503 123ms 30 Nov 2023 907th RedzGoose 🇦🇺 822 503 106ms 13 Oct 2024 910th Juanaco123 822 527 118ms 11 Dec 2025 911th CatsAreFluffy 821 410 54ms 30 Oct 2022 912th iamsolarpowered 821 463 33ms 16 Dec 2017 912th PikeIt 821 463 36ms 27 Jun 2023 914th JOrE20 821 487 1,454ms 30 Jan 2026 915th Adix-null 🇱🇹 821 506 414ms 30 Nov 2025 916th DaCoolOne 821 519 1ms 21 Nov 2019 916th SamHoque 821 519 1ms 11 May 2021 918th eMGeeneer 821 545 432ms 15 Jun 2024 919th GolfingSuccess 🇬🇷 820 426 40ms 31 Jul 2022 919th CaedenHarper 🇨🇦 820 426 42ms 2 hours ago 921st emgordon154 820 468 151ms 10 Aug 2024 922nd fuzzylojik-golf 🇺🇸 820 473 416ms 6 Jul 2025 923rd krzydoug 820 475 252ms 5 Jun 2020 924th passsy 🇩🇪 820 504 103ms 17 Nov 2022 925th Tviljan 🇫🇮 820 507 416ms 21 Nov 2021 925th cryptoriddlerUIO 820 507 425ms 24 Feb 2025 927th Attero 🇸🇪 820 508 1ms 30 Oct 2020 927th kdx2a 820 508 1ms 12 Feb 2025 929th msbranicky 820 520 1ms 12 Oct 2023 930th mattiapenati 820 551 160ms 28 Nov 2020 930th mad4j 🇮🇹 820 551 144ms 3 Jul 2021 932nd GrayJoKing 🇦🇺 819 463 3ms 15 Mar 2023 933rd DaCuteRaccoon 819 464 38ms 5 May 2022 934th JoeBigToe 819 476 263ms 5 Jun 2020 935th josh18994 819 490 8ms 8 Dec 2021 935th non-bin 819 490 9ms 27 Jun 2025 937th MeWhenI 🇻🇦 819 537 457ms 29 Nov 2022 937th tailorspy 819 537 455ms 28 Oct 2023 937th 09cf 819 537 472ms 29 Dec 2023 940th 21Joakim 818 491 9ms 30 Mar 2021 940th maxpelic 🇺🇸 818 491 10ms 8 Jul 2022 940th acollett89 818 491 9ms 18 Jun 2025 943rd shawaa 818 508 394ms 10 Jun 2020 943rd roavin 818 508 375ms 5 Jun 2022 943rd billings7 🇬🇧 818 508 387ms 29 Dec 2022 946th MeWhenI 🇻🇦 818 509 1ms 29 Nov 2022 946th TeodorDyakov 🇧🇬 818 509 1ms 7 Sep 2025 948th TetraPengwin 818 521 1ms 11 Feb 2022 949th aDwarfNamedUrist 818 552 129ms 21 Dec 2022 950th PalmEmanuel 817 477 275ms 10 May 2021 951st mousetail 🇳🇱 817 494 5ms 29 Dec 2025 952nd JDiLenarda 🇫🇷 817 508 1,309ms 7 Oct 2020 953rd MichalMarsalek 🇨🇿 817 522 1ms 11 Aug 2024 953rd TheDrawingCoder-Gamer 817 522 1ms 3 Jul 2025 955th SubsTheTechnomancer 817 529 120ms 28 Mar 2023 955th snoozingnewt 🇨🇦 817 529 116ms 23 Sep 2023 955th neel11235813 817 529 118ms 26 Mar 2024 958th vaughad 817 530 99ms 18 Jan 2020 958th nicholas-vella 817 530 101ms 26 Jan 2020 958th The-Wolfson 817 530 134ms 22 Dec 2024 First Prev 881–960 of 4,086 Next Last