The Calendar hole will go live in approximately 11 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 555th sean-niemann 🇺🇸 886 65 168ms 9 Jun 2025 562nd stefangimmillaro 886 71 91ms 2 Oct 2022 562nd Steffan153 🇫🇮 886 71 96ms 23 Feb 2023 562nd Shanethegamer 🇺🇸 886 71 90ms 16 May 2023 562nd sean-niemann 🇺🇸 886 71 89ms 12 Jul 2024 566th Shanethegamer 🇺🇸 886 72 90ms 8 May 2025 566th edsrzf 🇳🇿 886 72 103ms 4 Jul 2025 566th Yewzir 🇧🇪 886 72 92ms 20 Nov 2025 569th DialFrost 🇸🇬 886 95 29ms 10 Dec 2024 570th canissimia 🇦🇶 886 110 2,640ms 20 Feb 2023 571st GrayJoKing 🇦🇺 885 77 96ms 13 Sep 2024 572nd Steffan153 🇫🇮 884 52 7ms 31 Dec 2022 573rd albanian-laundromat 884 94 415ms 24 Sep 2025 573rd jkelly467 884 94 544ms 23 Oct 2025 573rd HumanoidCPU 884 94 397ms 8 Nov 2025 576th DialFrost 🇸🇬 883 76 81ms 17 Mar 2025 577th stefangimmillaro 882 53 56ms 2 Oct 2022 577th Haksell 🇦🇶 882 53 46ms 22 Feb 2023 579th GrayJoKing 🇦🇺 882 70 3ms 6 May 2022 579th ovs-code 🇩🇪 882 70 2ms 8 Oct 2023 579th 09cf 882 70 2ms 8 Oct 2023 579th saito-ta 🇯🇵 882 70 2ms 21 Dec 2023 579th sean-niemann 🇺🇸 882 70 2ms 10 Jul 2024 579th KasperKivimaeki 🇫🇮 882 70 6ms 8 Aug 2025 585th primo-ppcg 🇹🇭 882 85 39ms 14 Jan 2025 585th MeWhenI 🇻🇦 882 85 41ms 21 Apr 2025 587th SiestaGuru 882 88 326ms 9 Jan 2023 587th rifatx 882 88 322ms 5 Jul 2024 587th kmathis22 882 88 367ms 25 Sep 2025 587th arcpolaris 882 88 391ms 8 Nov 2025 591st primo-ppcg 🇹🇭 881 52 297ms 5 May 2022 591st dvargas46 🇺🇸 881 52 92ms 22 Dec 2022 593rd DialFrost 🇸🇬 881 56 863ms 1 Sep 2025 594th ovs-code 🇩🇪 881 89 438ms 24 Jul 2024 594th jipsong 🇩🇪 881 89 467ms 7 Apr 2025 596th nipzu 881 94 116ms 17 May 2022 596th Natanaelel 🇸🇪 881 94 125ms 17 Jun 2022 596th nkoppel 881 94 120ms 19 Oct 2022 596th ovs-code 🇩🇪 881 94 120ms 21 Jun 2023 596th mousetail 🇳🇱 881 94 124ms 12 Jan 2024 601st snoozingnewt 🇨🇦 881 95 109ms 16 days ago 602nd Irratix 🇳🇱 881 96 57ms 4 May 2022 602nd MeWhenI 🇻🇦 881 96 83ms 1 Jun 2022 602nd janbehrens 🇩🇪 881 96 57ms 21 Apr 2023 602nd Shanethegamer 🇺🇸 881 96 69ms 15 May 2023 602nd Yewzir 🇧🇪 881 96 81ms 11 Nov 2023 602nd MateuszPietrzak 🇵🇱 881 96 61ms 18 Nov 2023 602nd kkoenig 881 96 59ms 21 Dec 2023 602nd BlankSpruce 881 96 85ms 20 Aug 2024 602nd fuzzylojik-golf 🇺🇸 881 96 86ms 14 Jun 2025 611th m-tkach 🇺🇦 881 112 118ms 22 Jun 2025 612th sisyphus-ppcg 🇦🇺 880 40 383ms 31 Jan 2023 612th sean-niemann 🇺🇸 880 40 507ms 8 Mar 2025 614th ovs-code 🇩🇪 880 73 340ms 22 Jul 2023 615th sean-niemann 🇺🇸 880 108 274ms 25 May 2024 615th GolfingSuccess 🇬🇷 880 108 273ms 6 Sep 2025 617th GrayJoKing 🇦🇺 879 72 426ms 31 May 2022 617th Shanethegamer 🇺🇸 879 72 411ms 1 Jun 2022 617th Steffan153 🇫🇮 879 72 413ms 10 Dec 2022 620th steffan-polygolf 879 74 136ms 14 Feb 2024 620th prestosilver 🇺🇸 879 74 124ms 2 days ago 622nd Shanethegamer 🇺🇸 879 81 17ms 19 Dec 2023 622nd emgordon154 879 81 31ms 29 Jul 2025 624th primo-ppcg 🇹🇭 878 193 107ms 14 Aug 2025 625th Shanethegamer 🇺🇸 877 142 511ms 27 Mar 2025 625th DialFrost 🇸🇬 877 142 490ms 28 Mar 2025 625th emgordon154 877 142 395ms 10 Apr 2025 625th GolfingSuccess 🇬🇷 877 142 463ms 14 days ago 629th mousetail 🇳🇱 876 40 66ms 29 Aug 2025 630th GrayJoKing 🇦🇺 876 84 37ms 19 Jun 2022 630th primo-ppcg 🇹🇭 876 84 36ms 29 Jun 2022 632nd Shanethegamer 🇺🇸 875 51 428ms 15 May 2023 633rd Grrisly 875 74 4ms 25 Mar 2024 634th JayXon 🇺🇸 875 157 1,772ms 14 Sep 2025 635th rucin93 🇵🇱 874 57 136ms 4 Aug 2024 635th dokutan 874 57 129ms 9 Aug 2024 637th c0d3-4-F00d 🇩🇪 874 61 10ms 6 May 2022 637th jackkav 874 61 10ms 26 Jun 2022 637th TechNolaByte 874 61 10ms 6 Jul 2022 637th Heathcorp 🇦🇺 874 61 9ms 17 Jul 2022 First Prev 561–640 of 3,505 Next Last