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 chars. 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 Chars Time Submitted 161st Lydxn 🇨🇦 913 186 65ms 2 Jul 2023 162nd emgordon154 913 203 465ms 14 Apr 2025 162nd albanian-laundromat 913 203 396ms 30 Oct 2025 164th m42km 913 207 17ms 4 Feb 2024 164th abhishekg999 913 207 17ms 21 Sep 2024 166th MeWhenI 🇻🇦 913 373 114ms 11 Apr 2024 167th Argeento 🇵🇱 912 236 14ms 29 Sep 2020 167th taylorzane 912 236 13ms 11 Aug 2022 169th jared-hughes 912 404 7ms 12 Nov 2023 170th sean-niemann 🇺🇸 911 247 1ms 14 Jul 2025 171st primo-ppcg 🇹🇭 911 335 121ms 21 Jan 2020 171st stefangimmillaro 911 335 129ms 19 Aug 2023 173rd dokutan 911 430 9ms 6 Oct 2024 174th MeWhenI 🇻🇦 910 219 11ms 9 May 2024 175th nwellnhof 🇩🇪 910 433 4ms 23 Oct 2024 176th snoozingnewt 🇨🇦 909 203 36ms 14 Oct 2025 177th SirBogman 🇺🇸 908 204 413ms 24 Jan 2024 177th dokutan 908 204 393ms 14 Feb 2026 179th ETHproductions 🇺🇸 908 237 10ms 19 Dec 2018 179th voytxt 🇨🇿 908 237 11ms 20 Mar 2022 179th two-bad 🇬🇧 908 237 12ms 2 Feb 2024 179th emgordon154 908 237 17ms 1 Aug 2024 179th JOrE20 908 237 13ms 24 Nov 2025 184th snoozingnewt 🇨🇦 908 334 125ms 17 Dec 2025 185th canissimia 🇦🇶 907 1,785 2ms 28 Dec 2021 186th sean-niemann 🇺🇸 906 270 3ms 22 Aug 2025 187th GrayJoKing 🇦🇺 906 423 3ms 18 Aug 2024 188th MeWhenI 🇻🇦 906 424 7ms 31 Dec 2024 189th m-tkach 🇺🇦 905 499 26ms 29 Sep 2023 190th FlorianCassayre 🇫🇷 904 209 17ms 18 Sep 2023 190th Openstreetmapler 904 209 17ms 6 May 2025 192nd akshatj27 🇦🇶 904 238 12ms 11 Jan 2022 193rd synt7x 🇺🇸 904 249 2ms 5 Jul 2025 194th o0lit3 🇺🇸 901 173 6ms 24 Mar 2021 195th richard-oelze 🇩🇪 901 239 11ms 24 Jul 2025 196th Shanethegamer 🇺🇸 901 425 5ms 19 Apr 2025 197th inventshah 901 437 2ms 11 Sep 2023 198th MeWhenI 🇻🇦 901 501 26ms 7 Jun 2023 199th marshallward 🇺🇸 901 504 40ms 27 Dec 2024 200th Baroniket 900 210 17ms 13 Aug 2025 200th robin-scragg 900 210 16ms 20 Sep 2025 200th vhoulbreque 🇫🇷 900 210 18ms 30 Nov 2025 203rd GrayJoKing 🇦🇺 899 502 28ms 4 Jan 2023 204th Mukundan314 898 340 213ms 9 Jul 2025 205th taklam 897 240 10ms 2 Jul 2020 205th CatsAreFluffy 897 240 11ms 18 Dec 2022 205th tayloia 🇬🇧 897 240 17ms 18 Jul 2023 208th primo-ppcg 🇹🇭 897 506 41ms 24 May 2025 209th prplz 🇦🇺 897 553 1,786ms 25 Apr 2024 210th Yewzir 🇧🇪 896 211 16ms 7 Oct 2023 211th emgordon154 895 428 4ms 8 Sep 2025 212th primo-ppcg 🇹🇭 895 438 4ms 2 May 2023 213th prplz 🇦🇺 894 371 216ms 9 Jan 2020 214th Re-Adventures 🇮🇳 893 241 13ms 28 Nov 2021 214th dscholtz-lab49 893 241 18ms 23 May 2023 214th HumanoidCPU 893 241 11ms 5 May 2024 217th dokutan 893 249 2ms 26 Dec 2025 218th adriweb 🇫🇷 893 252 85ms 1 Jan 2024 218th FlyingPenguin223 893 252 1ms 11 Dec 2024 220th primo-ppcg 🇹🇭 893 650 14ms 13 Aug 2025 221st Shanethegamer 🇺🇸 892 207 34ms 8 Aug 2021 222nd wh3n3v3r 🇨🇿 892 212 17ms 7 Nov 2024 223rd Alex-x90 🇺🇸 891 297 121ms 11 Jan 2023 224th typeswitch-dev 🇵🇹 889 517 3ms 22 Aug 2025 225th JunkIce 887 213 10ms 29 Mar 2025 225th Matter1024 🇮🇳 887 213 17ms 8 days ago 227th GrayJoKing 🇦🇺 887 518 3ms 23 Jul 2023 228th helbling 🇨🇭 886 243 14ms 4 Feb 2024 229th Shanethegamer 🇺🇸 886 254 2ms 1 Jun 2022 230th MeWhenI 🇻🇦 885 235 41ms 4 Sep 2024 231st andersk 🇺🇸 885 375 225ms 22 Oct 2022 232nd primo-ppcg 🇹🇭 885 395 17ms 6 Feb 2022 233rd prplz 🇦🇺 884 209 313ms 1 Jul 2020 234th JOrE20 883 214 15ms 24 Feb 2026 235th ovs-code 🇩🇪 883 434 4ms 5 Oct 2024 236th MeWhenI 🇻🇦 883 446 2ms 13 Mar 2025 237th BlankSpruce 883 562 1,627ms 15 Sep 2025 238th Yewzir 🇧🇪 882 210 417ms 4 Feb 2024 239th SirBogman 🇺🇸 882 515 40ms 1 Jun 2024 240th Yewzir 🇧🇪 881 563 1,730ms 1 Jun 2024 First Prev 161–240 of 4,056 Next Last