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 881st lynn 845 96 29ms 11 Jul 2023 882nd Shanethegamer 🇺🇸 845 98 119ms 26 Oct 2022 882nd emgordon154 845 98 121ms 18 Feb 2025 884th janAkali 🇷🇺 844 77 123ms 12 Feb 2025 885th bschorno 844 92 366ms 12 Oct 2022 885th ChrisTheisen 844 92 339ms 14 Dec 2022 885th kellantech 844 92 363ms 4 Jul 2023 885th Mezzofloat 844 92 377ms 26 Aug 2023 885th Maximizer02 844 92 360ms 1 Oct 2023 885th madeforlosers 844 92 365ms 21 Nov 2024 885th ChromaChroma 844 92 354ms 7 Oct 2025 885th snoozingnewt 🇨🇦 844 92 379ms 8 Oct 2025 893rd DialFrost 🇸🇬 843 66 107ms 7 Apr 2025 893rd KasperKivimaeki 🇫🇮 843 66 9ms 13 hours ago 895th dokutan 843 93 428ms 27 Sep 2025 896th krcs 🇵🇱 842 53 282ms 9 May 2022 896th ryanlanegit 842 53 301ms 19 Jun 2022 896th sisyphus-ppcg 🇦🇺 842 53 456ms 15 Aug 2022 899th MeWhenI 🇻🇦 842 71 106ms 13 Dec 2022 900th SirBogman 🇺🇸 842 89 38ms 4 May 2022 901st error256 841 81 71ms 13 Sep 2024 902nd CLOStrophobic 🇮🇹 841 89 42ms 14 Feb 2025 903rd kmathis22 841 100 31ms 13 Nov 2025 904th raszpi 🇭🇺 840 77 103ms 1 Sep 2023 905th eshilo-draper 839 75 86ms 6 Sep 2022 905th kmathis22 839 75 79ms 5 Sep 2025 907th sean-niemann 🇺🇸 839 76 107ms 8 Oct 2024 908th beardotpdf 839 99 346ms 10 days ago 909th emplv 🇱🇻 839 124 25ms 31 Oct 2022 910th Codsilla 🇨🇦 838 51 266ms 1 Jul 2022 911th frankgraziano 838 66 4ms 20 Apr 2025 912th Andriamanitra 🇫🇮 838 83 12ms 17 Apr 2023 912th Natanaelel 🇸🇪 838 83 12ms 8 Jul 2023 914th MeWhenI 🇻🇦 838 164 1,639ms 7 Nov 2025 915th ovs-code 🇩🇪 837 85 15ms 11 Dec 2023 916th dokutan 837 88 39ms 9 Jun 2024 917th Steffan153 🇫🇮 837 97 29ms 18 Jan 2023 918th CatsAreFluffy 837 101 54ms 18 Feb 2023 918th annaproxy 837 101 70ms 9 May 2023 918th wojtekmal 837 101 78ms 15 Nov 2023 918th HumanoidCPU 837 101 83ms 6 May 2024 918th eMGeeneer 837 101 449ms 27 Jun 2024 918th bac0id 837 101 77ms 29 Jun 2024 918th michaelmoynihan 837 101 508ms 3 Sep 2025 918th snoozingnewt 🇨🇦 837 101 517ms 6 Oct 2025 926th SirBogman 🇺🇸 835 36 14ms 5 May 2022 926th Natanaelel 🇸🇪 835 36 87ms 15 Jun 2022 926th Steffan153 🇫🇮 835 36 91ms 18 Jan 2023 926th codereport 🇨🇦 835 36 9ms 1 Jun 2024 926th GolfinK 835 36 9ms 21 Nov 2024 926th lifthrasiir 🇰🇷 835 36 10ms 1 Dec 2024 926th GolfingSuccess 🇬🇷 835 36 11ms 20 Mar 2025 933rd scpchicken 🇵🇼 835 55 10ms 4 May 2022 933rd SirBogman 🇺🇸 835 55 6ms 5 May 2022 933rd Shanethegamer 🇺🇸 835 55 6ms 19 May 2023 933rd DialFrost 🇸🇬 835 55 10ms 14 Feb 2025 937th ChiefChippy2 835 56 51ms 4 May 2022 937th aksyristos 835 56 42ms 29 Jan 2023 937th anter69 🇭🇺 835 56 38ms 12 Feb 2024 937th 3dm4n 🇫🇮 835 56 38ms 11 Mar 2024 937th lgrandco 835 56 43ms 9 Oct 2024 937th tatzyr 🇯🇵 835 56 43ms 10 Dec 2024 937th D-MOVE 🇵🇭 835 56 49ms 14 days ago 944th inverseLorentz 🇦🇺 835 69 156ms 3 Jun 2024 944th Yewzir 🇧🇪 835 69 118ms 24 Dec 2024 944th CLOStrophobic 🇮🇹 835 69 170ms 28 May 2025 947th p-vf 🇨🇭 835 93 337ms 24 Jun 2022 947th Smetalo 835 93 384ms 25 Aug 2022 947th malworthy 835 93 360ms 19 Aug 2024 950th moustave 834 67 23ms 7 Nov 2024 951st Alex-x90 🇺🇸 834 74 2ms 4 Dec 2022 951st undersquire 834 74 2ms 24 Jun 2023 951st rdmsr 834 74 2ms 24 Jun 2023 951st Bmrl7 834 74 2ms 9 Jul 2023 951st Vinterion 834 74 4ms 6 Nov 2023 951st namelessiw 834 74 2ms 28 Dec 2023 951st Jonatan6 🇩🇰 834 74 2ms 15 Mar 2024 951st Mandrzejy 🇵🇱 834 74 2ms 12 Apr 2024 951st kaurakeksi 🇫🇮 834 74 2ms 29 Dec 2024 960th Shanethegamer 🇺🇸 834 82 141ms 15 May 2023 First Prev 881–960 of 3,472 Next Last