The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 9 hours. Why not try and solve them ahead of time?
Collatz 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 151st AdrienHache 🇫🇷 939 83 420ms 8 Jun 2023 151st gblikas 939 83 412ms 23 Jul 2023 151st KrausRaus 🇺🇸 939 83 392ms 31 Jul 2023 151st namelessiw 939 83 396ms 9 Apr 2025 151st dokutan 939 83 391ms 9 Apr 2025 151st m-tkach 🇺🇦 939 83 411ms 10 Apr 2025 151st DialFrost 🇸🇬 939 83 401ms 10 Apr 2025 151st kylejcwu 939 83 374ms 19 Apr 2025 151st Tyrant7 939 83 409ms 19 Apr 2025 151st Yax42 🇫🇷 939 83 442ms 19 Apr 2025 151st MeWhenI 🇻🇦 939 83 378ms 19 Jun 2025 151st sean-niemann 🇺🇸 939 83 390ms 20 Jun 2025 151st stefangimmillaro 939 83 391ms 20 Jun 2025 151st tomh1012 939 83 418ms 28 Aug 2025 151st fuzzylojik-golf 🇺🇸 939 83 389ms 8 Sep 2025 151st CaedenHarper 🇨🇦 939 83 377ms 17 Oct 2025 151st arcpolaris 939 83 421ms 13 Jan 2026 151st amazingalek 🇳🇴 939 83 403ms 21 Jan 2026 179th grey0ut 938 48 2,086ms 8 Apr 2025 180th GolfingSuccess 🇬🇷 938 49 38ms 12 Aug 2024 180th Shanethegamer 🇺🇸 938 49 39ms 12 Aug 2024 180th Steffan153 🇫🇮 938 49 39ms 12 Aug 2024 180th MeWhenI 🇻🇦 938 49 37ms 13 Aug 2024 180th DialFrost 🇸🇬 938 49 38ms 13 Aug 2024 180th GrayJoKing 🇦🇺 938 49 41ms 15 Aug 2024 180th btnlq 938 49 39ms 16 Aug 2024 180th emgordon154 938 49 41ms 19 Aug 2024 180th ovs-code 🇩🇪 938 49 39ms 19 Aug 2024 180th mousetail 🇳🇱 938 49 39ms 13 Sep 2024 180th lynn 938 49 39ms 20 Dec 2024 180th weeble 938 49 40ms 20 Dec 2024 180th sean-niemann 🇺🇸 938 49 39ms 11 Jan 2025 193rd JayXon 🇺🇸 937 66 1,308ms 18 Nov 2025 194th DialFrost 🇸🇬 937 89 513ms 24 Sep 2025 194th ovs-code 🇩🇪 937 89 474ms 24 Sep 2025 194th dokutan 937 89 372ms 24 Sep 2025 194th sean-niemann 🇺🇸 937 89 397ms 24 Sep 2025 194th Shanethegamer 🇺🇸 937 89 477ms 25 Sep 2025 194th nwellnhof 🇩🇪 937 89 454ms 25 Sep 2025 194th m-tkach 🇺🇦 937 89 386ms 25 Sep 2025 194th namelessiw 937 89 390ms 2 Oct 2025 194th Yewzir 🇧🇪 937 89 349ms 2 Oct 2025 194th Yax42 🇫🇷 937 89 496ms 4 Oct 2025 194th stefangimmillaro 937 89 489ms 6 Oct 2025 194th CaedenHarper 🇨🇦 937 89 467ms 9 Oct 2025 194th Jacob385 937 89 491ms 27 Oct 2025 194th MeWhenI 🇻🇦 937 89 449ms 7 Nov 2025 194th ethanlally 937 89 380ms 10 Nov 2025 194th snoozingnewt 🇨🇦 937 89 384ms 23 Nov 2025 194th ScottHamper 937 89 467ms 30 Nov 2025 194th KasperKivimaeki 🇫🇮 937 89 444ms 30 Nov 2025 212th JayXon 🇺🇸 935 73 4ms 23 Dec 2025 213th nwellnhof 🇩🇪 933 42 458ms 4 May 2022 213th Lydxn 🇨🇦 933 42 1,649ms 4 May 2022 213th GrayJoKing 🇦🇺 933 42 424ms 4 May 2022 213th Steffan153 🇫🇮 933 42 398ms 16 Dec 2022 213th sisyphus-ppcg 🇦🇺 933 42 422ms 31 Jan 2023 213th ovs-code 🇩🇪 933 42 449ms 30 Dec 2023 213th sean-niemann 🇺🇸 933 42 444ms 8 Mar 2025 220th emplv 🇱🇻 933 60 10ms 5 May 2022 220th GrayJoKing 🇦🇺 933 60 9ms 6 May 2022 220th targrik 933 60 9ms 24 Dec 2024 220th xsot 🇸🇬 933 60 10ms 1 May 2025 224th m-tkach 🇺🇦 933 91 61ms 5 May 2022 224th 09cf 933 91 56ms 4 Oct 2023 226th GrayJoKing 🇦🇺 932 56 437ms 15 Jan 2024 226th AlephSquirrel 932 56 396ms 21 Jan 2024 226th CaedenHarper 🇨🇦 932 56 484ms 26 Jan 2026 229th Steffan153 🇫🇮 931 51 2,377ms 12 days ago 230th ovs-code 🇩🇪 931 60 5ms 9 Oct 2023 230th GrayJoKing 🇦🇺 931 60 4ms 11 Oct 2023 230th Lydxn 🇨🇦 931 60 5ms 11 Oct 2023 230th GolfingSuccess 🇬🇷 931 60 5ms 16 Nov 2023 230th Steffan153 🇫🇮 931 60 5ms 28 Jan 2024 230th JayXon 🇺🇸 931 60 4ms 29 Jan 2024 230th rucin93 🇵🇱 931 60 5ms 10 Jul 2024 230th sean-niemann 🇺🇸 931 60 5ms 10 Jul 2024 230th edsrzf 🇳🇿 931 60 5ms 21 days ago 239th MeWhenI 🇻🇦 931 68 98ms 23 Feb 2023 239th JayXon 🇺🇸 931 68 98ms 4 Mar 2025 First Prev 161–240 of 3,649 Next Last