The Calendar hole will go live in approximately 6 days. Why not try and solve it ahead of time?
Collatz 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 Card Number Validation Catalan Numbers Catalan’s Constant Christmas Trees Collatz 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 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 Apéry’s Constant Binary Lambda Calculus Calendar Connect Four Continued Fractions Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers Multitap Input NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial All Languages ><> 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 ALGOL 68 APL Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight Luau Odin Picat Qore Racket Rebol Rexx Scala Squirrel Stax Uiua Umka Vala Vyxal Bytes Chars Scoring Bytes Chars Language All ><> 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 ALGOL 68 APL Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight 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 Card Number Validation Catalan Numbers Catalan’s Constant Christmas Trees Collatz 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 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 Apéry’s Constant Binary Lambda Calculus Calendar Connect Four Continued Fractions Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers Multitap Input NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial # Golfer Points Chars Time Submitted 558th sean-niemann 🇺🇸 886 71 89ms 12 Jul 2024 562nd Shanethegamer 🇺🇸 886 72 90ms 8 May 2025 562nd edsrzf 🇳🇿 886 72 103ms 4 Jul 2025 562nd Yewzir 🇧🇪 886 72 92ms 20 Nov 2025 565th DialFrost 🇸🇬 886 95 29ms 10 Dec 2024 566th canissimia 🇦🇶 886 110 2,640ms 20 Feb 2023 567th GrayJoKing 🇦🇺 885 77 76ms 13 Sep 2024 568th Steffan153 🇫🇮 884 52 7ms 31 Dec 2022 569th albanian-laundromat 884 94 415ms 24 Sep 2025 569th jkelly467 884 94 544ms 23 Oct 2025 569th HumanoidCPU 884 94 397ms 8 Nov 2025 572nd DialFrost 🇸🇬 883 76 81ms 17 Mar 2025 573rd stefangimmillaro 882 53 40ms 2 Oct 2022 573rd Haksell 🇦🇶 882 53 40ms 22 Feb 2023 575th GrayJoKing 🇦🇺 882 70 3ms 6 May 2022 575th ovs-code 🇩🇪 882 70 2ms 8 Oct 2023 575th 09cf 882 70 2ms 8 Oct 2023 575th saito-ta 🇯🇵 882 70 2ms 21 Dec 2023 575th sean-niemann 🇺🇸 882 70 2ms 10 Jul 2024 575th KasperKivimaeki 🇫🇮 882 70 6ms 8 Aug 2025 581st primo-ppcg 🇹🇭 882 85 39ms 14 Jan 2025 581st MeWhenI 🇻🇦 882 85 41ms 21 Apr 2025 583rd SiestaGuru 882 88 326ms 9 Jan 2023 583rd rifatx 882 88 322ms 5 Jul 2024 583rd kmathis22 882 88 346ms 25 Sep 2025 583rd arcpolaris 882 88 371ms 8 Nov 2025 587th primo-ppcg 🇹🇭 881 52 219ms 5 May 2022 587th dvargas46 🇺🇸 881 52 91ms 22 Dec 2022 589th DialFrost 🇸🇬 881 56 863ms 1 Sep 2025 590th ovs-code 🇩🇪 881 89 438ms 24 Jul 2024 590th jipsong 🇩🇪 881 89 467ms 7 Apr 2025 590th DialFrost 🇸🇬 881 89 394ms 44 hours ago 593rd nipzu 881 94 116ms 17 May 2022 593rd Natanaelel 🇸🇪 881 94 125ms 17 Jun 2022 593rd nkoppel 881 94 120ms 19 Oct 2022 593rd ovs-code 🇩🇪 881 94 120ms 21 Jun 2023 593rd mousetail 🇳🇱 881 94 124ms 12 Jan 2024 598th snoozingnewt 🇨🇦 881 95 109ms 21 days ago 599th Irratix 🇳🇱 881 96 57ms 4 May 2022 599th MeWhenI 🇻🇦 881 96 58ms 1 Jun 2022 599th janbehrens 🇩🇪 881 96 57ms 21 Apr 2023 599th Shanethegamer 🇺🇸 881 96 69ms 15 May 2023 599th Yewzir 🇧🇪 881 96 67ms 11 Nov 2023 599th MateuszPietrzak 🇵🇱 881 96 60ms 18 Nov 2023 599th kkoenig 881 96 59ms 21 Dec 2023 599th BlankSpruce 881 96 60ms 20 Aug 2024 599th fuzzylojik-golf 🇺🇸 881 96 86ms 14 Jun 2025 608th m-tkach 🇺🇦 881 112 118ms 22 Jun 2025 609th sisyphus-ppcg 🇦🇺 880 40 389ms 31 Jan 2023 609th sean-niemann 🇺🇸 880 40 399ms 8 Mar 2025 611th ovs-code 🇩🇪 880 73 340ms 22 Jul 2023 612th sean-niemann 🇺🇸 880 108 274ms 25 May 2024 612th GolfingSuccess 🇬🇷 880 108 273ms 6 Sep 2025 614th GrayJoKing 🇦🇺 879 72 426ms 31 May 2022 614th Shanethegamer 🇺🇸 879 72 411ms 1 Jun 2022 614th Steffan153 🇫🇮 879 72 413ms 10 Dec 2022 617th steffan-polygolf 879 74 136ms 14 Feb 2024 617th prestosilver 🇺🇸 879 74 124ms 7 days ago 619th Shanethegamer 🇺🇸 879 81 17ms 19 Dec 2023 619th emgordon154 879 81 31ms 29 Jul 2025 621st primo-ppcg 🇹🇭 878 193 107ms 14 Aug 2025 622nd Shanethegamer 🇺🇸 877 142 511ms 27 Mar 2025 622nd DialFrost 🇸🇬 877 142 490ms 28 Mar 2025 622nd emgordon154 877 142 395ms 10 Apr 2025 622nd GolfingSuccess 🇬🇷 877 142 463ms 19 days ago 626th mousetail 🇳🇱 876 40 66ms 29 Aug 2025 627th GrayJoKing 🇦🇺 876 84 37ms 19 Jun 2022 627th primo-ppcg 🇹🇭 876 84 36ms 29 Jun 2022 629th Shanethegamer 🇺🇸 875 51 426ms 15 May 2023 630th JayXon 🇺🇸 875 157 1,772ms 14 Sep 2025 631st rucin93 🇵🇱 874 57 136ms 4 Aug 2024 631st dokutan 874 57 129ms 9 Aug 2024 633rd c0d3-4-F00d 🇩🇪 874 61 10ms 6 May 2022 633rd jackkav 874 61 10ms 26 Jun 2022 633rd TechNolaByte 874 61 10ms 6 Jul 2022 633rd Heathcorp 🇦🇺 874 61 9ms 17 Jul 2022 633rd C0de5mith 🇺🇸 874 61 11ms 3 Aug 2022 633rd sebipopa 🇷🇴 874 61 10ms 18 Aug 2022 633rd moikaturns 🇬🇧 874 61 9ms 25 Sep 2022 633rd FlorianCassayre 🇫🇷 874 61 10ms 27 Sep 2022 First Prev 561–640 of 3,481 Next Last