The Calendar hole will go live in approximately 8 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 721st DialFrost 🇸🇬 864 64 5ms 10 Jul 2024 722nd emplv 🇱🇻 864 110 296ms 5 May 2022 722nd Shanethegamer 🇺🇸 864 110 261ms 21 Nov 2023 722nd edsrzf 🇳🇿 864 110 258ms 28 Nov 2024 722nd targrik 864 110 267ms 30 Jun 2025 726th TylerBloom 863 96 115ms 22 Mar 2024 727th Shanethegamer 🇺🇸 863 97 100ms 15 Apr 2025 727th GolfingSuccess 🇬🇷 863 97 111ms 25 days ago 727th DialFrost 🇸🇬 863 97 94ms 21 days ago 730th shellbertt 🇨🇦 863 98 66ms 9 May 2022 730th iakolzin 863 98 85ms 26 May 2022 730th Betuaredead 863 98 78ms 5 Jan 2023 730th oceko 863 98 73ms 19 Feb 2024 730th dokutan 863 98 81ms 17 Mar 2024 730th cuzdav 863 98 62ms 4 May 2025 730th timhaj 🇸🇮 863 98 82ms 12 Sep 2025 730th Yax42 🇫🇷 863 98 75ms 4 Oct 2025 738th Steffan153 🇫🇮 862 82 1,287ms 23 Feb 2023 739th deadp4nda 🇩🇪 862 90 372ms 26 Apr 2024 739th 123mjb 862 90 352ms 23 Jun 2025 739th michelebastione 🇮🇹 862 90 384ms 24 Aug 2025 739th razvandmtr 🇷🇴 862 90 385ms 6 Nov 2025 739th amazingalek 862 90 429ms 2 days ago 744th steffan-polygolf 861 73 87ms 23 Feb 2023 744th MWI-polygolf 861 73 83ms 6 Dec 2023 744th HumanoidCPU 861 73 81ms 7 May 2024 747th Steffan153 🇫🇮 861 78 80ms 4 Feb 2023 748th GrayJoKing 🇦🇺 860 56 411ms 15 Jan 2024 748th AlephSquirrel 860 56 426ms 21 Jan 2024 750th Setvizan 860 62 10ms 12 Jan 2023 750th GreenBeansAgainstVeganism 860 62 10ms 13 Jan 2023 750th arctouch-cristiannevianna 860 62 10ms 3 Apr 2023 750th Corxldyphik 860 62 10ms 11 Apr 2023 750th Blockyheadman 860 62 10ms 1 Nov 2023 750th ollyspooner 860 62 10ms 22 Nov 2023 750th itserasmus 860 62 10ms 25 Jan 2024 750th Jacob385 860 62 10ms 13 Mar 2024 750th junkondo-jp 860 62 11ms 30 Jun 2024 750th ShiraJoseph 🇺🇸 860 62 9ms 1 Mar 2025 750th tomh1012 860 62 9ms 20 days ago 761st yzhs 🇩🇪 860 65 19ms 16 Jun 2022 761st rollershutter 860 65 20ms 9 Sep 2022 761st bac0id 860 65 20ms 26 Sep 2023 761st robin-scragg 860 65 23ms 8 Jun 2025 761st RaBa21 🇭🇺 860 65 29ms 11 Jul 2025 761st TransformLikeATensor 860 65 20ms 17 Oct 2025 767th Andriamanitra 🇫🇮 860 67 144ms 26 Apr 2023 768th MeWhenI 🇻🇦 859 81 8ms 23 May 2023 769th MeWhenI 🇻🇦 859 145 526ms 28 Mar 2025 770th ulucs 858 35 9ms 8 May 2022 770th bstrat 858 35 9ms 6 Jun 2024 770th wh3n3v3r 🇨🇿 858 35 8ms 18 Nov 2024 773rd JRaspass 🇬🇧 858 41 541ms 4 May 2022 773rd SirBogman 🇺🇸 858 41 264ms 4 May 2022 773rd Natanaelel 🇸🇪 858 41 326ms 4 May 2022 776th 5quiwyrm 858 52 300ms 4 Sep 2022 776th MeWhenI 🇻🇦 858 52 280ms 28 Jan 2023 776th Feniske 🇫🇷 858 52 280ms 7 Nov 2023 776th dcgjb 858 52 297ms 29 Jan 2024 776th JPRuskin 🇬🇧 858 52 313ms 7 Apr 2025 776th IISResetMe 858 52 267ms 7 Apr 2025 776th Ripick 858 52 266ms 1 Jun 2025 783rd Yewzir 🇧🇪 858 160 2,399ms 14 Nov 2025 784th jared-hughes 857 72 2ms 6 Jul 2022 784th Steffan153 🇫🇮 857 72 2ms 3 Jan 2023 784th MeWhenI 🇻🇦 857 72 3ms 7 May 2023 784th ListeriaM 857 72 2ms 22 Aug 2023 784th larcherMTT 857 72 2ms 5 Oct 2024 784th snyderek 🇺🇸 857 72 3ms 19 Feb 2025 784th 5quiwyrm 857 72 2ms 29 Jun 2025 784th TeodorDyakov 🇧🇬 857 72 3ms 8 Jul 2025 784th xiaoyiming123 857 72 2ms 12 Jul 2025 793rd Liibe 857 97 391ms 25 Sep 2025 793rd Schmitt-Very-Cool 857 97 435ms 26 Sep 2025 795th typeswitch-dev 🇵🇹 856 75 5ms 22 Jul 2023 796th ovs-code 🇩🇪 856 83 54ms 1 Jul 2024 797th 386asm 🇺🇸 856 86 40ms 9 Apr 2023 798th nwellnhof 🇩🇪 856 111 271ms 4 May 2022 798th stefangimmillaro 856 111 268ms 26 Sep 2023 798th kkoenig 856 111 287ms 4 Jan 2024 First Prev 721–800 of 3,472 Next Last