The Calendar hole will go live in approximately 10 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 556th tobeannouncd 886 65 312ms 25 Apr 2025 556th sean-niemann 🇺🇸 886 65 168ms 9 Jun 2025 563rd stefangimmillaro 886 71 91ms 2 Oct 2022 563rd Steffan153 🇫🇮 886 71 96ms 23 Feb 2023 563rd Shanethegamer 🇺🇸 886 71 90ms 16 May 2023 563rd sean-niemann 🇺🇸 886 71 89ms 12 Jul 2024 567th Shanethegamer 🇺🇸 886 72 90ms 8 May 2025 567th edsrzf 🇳🇿 886 72 103ms 4 Jul 2025 567th Yewzir 🇧🇪 886 72 92ms 20 Nov 2025 570th DialFrost 🇸🇬 886 95 29ms 10 Dec 2024 571st canissimia 🇦🇶 886 110 2,640ms 20 Feb 2023 572nd GrayJoKing 🇦🇺 885 77 96ms 13 Sep 2024 573rd Steffan153 🇫🇮 884 52 7ms 31 Dec 2022 574th albanian-laundromat 884 94 415ms 24 Sep 2025 574th jkelly467 884 94 544ms 23 Oct 2025 574th HumanoidCPU 884 94 397ms 8 Nov 2025 577th DialFrost 🇸🇬 883 76 81ms 17 Mar 2025 578th stefangimmillaro 882 53 56ms 2 Oct 2022 578th Haksell 🇦🇶 882 53 46ms 22 Feb 2023 580th GrayJoKing 🇦🇺 882 70 3ms 6 May 2022 580th ovs-code 🇩🇪 882 70 2ms 8 Oct 2023 580th 09cf 882 70 2ms 8 Oct 2023 580th saito-ta 🇯🇵 882 70 2ms 21 Dec 2023 580th sean-niemann 🇺🇸 882 70 2ms 10 Jul 2024 580th KasperKivimaeki 🇫🇮 882 70 6ms 8 Aug 2025 586th primo-ppcg 🇹🇭 882 85 39ms 14 Jan 2025 586th MeWhenI 🇻🇦 882 85 41ms 21 Apr 2025 588th SiestaGuru 882 88 326ms 9 Jan 2023 588th rifatx 882 88 322ms 5 Jul 2024 588th kmathis22 882 88 367ms 25 Sep 2025 588th arcpolaris 882 88 391ms 8 Nov 2025 592nd primo-ppcg 🇹🇭 881 52 297ms 5 May 2022 592nd dvargas46 🇺🇸 881 52 92ms 22 Dec 2022 594th DialFrost 🇸🇬 881 56 863ms 1 Sep 2025 595th ovs-code 🇩🇪 881 89 438ms 24 Jul 2024 595th jipsong 🇩🇪 881 89 467ms 7 Apr 2025 597th nipzu 881 94 116ms 17 May 2022 597th Natanaelel 🇸🇪 881 94 125ms 17 Jun 2022 597th nkoppel 881 94 120ms 19 Oct 2022 597th ovs-code 🇩🇪 881 94 120ms 21 Jun 2023 597th mousetail 🇳🇱 881 94 124ms 12 Jan 2024 602nd snoozingnewt 🇨🇦 881 95 109ms 17 days ago 603rd Irratix 🇳🇱 881 96 57ms 4 May 2022 603rd MeWhenI 🇻🇦 881 96 83ms 1 Jun 2022 603rd janbehrens 🇩🇪 881 96 57ms 21 Apr 2023 603rd Shanethegamer 🇺🇸 881 96 69ms 15 May 2023 603rd Yewzir 🇧🇪 881 96 81ms 11 Nov 2023 603rd MateuszPietrzak 🇵🇱 881 96 61ms 18 Nov 2023 603rd kkoenig 881 96 59ms 21 Dec 2023 603rd BlankSpruce 881 96 85ms 20 Aug 2024 603rd fuzzylojik-golf 🇺🇸 881 96 86ms 14 Jun 2025 612th m-tkach 🇺🇦 881 112 118ms 22 Jun 2025 613th sisyphus-ppcg 🇦🇺 880 40 383ms 31 Jan 2023 613th sean-niemann 🇺🇸 880 40 507ms 8 Mar 2025 615th ovs-code 🇩🇪 880 73 340ms 22 Jul 2023 616th sean-niemann 🇺🇸 880 108 274ms 25 May 2024 616th GolfingSuccess 🇬🇷 880 108 273ms 6 Sep 2025 618th GrayJoKing 🇦🇺 879 72 426ms 31 May 2022 618th Shanethegamer 🇺🇸 879 72 411ms 1 Jun 2022 618th Steffan153 🇫🇮 879 72 413ms 10 Dec 2022 621st steffan-polygolf 879 74 136ms 14 Feb 2024 621st prestosilver 🇺🇸 879 74 124ms 3 days ago 623rd Shanethegamer 🇺🇸 879 81 17ms 19 Dec 2023 623rd emgordon154 879 81 31ms 29 Jul 2025 625th primo-ppcg 🇹🇭 878 193 107ms 14 Aug 2025 626th Shanethegamer 🇺🇸 877 142 511ms 27 Mar 2025 626th DialFrost 🇸🇬 877 142 490ms 28 Mar 2025 626th emgordon154 877 142 395ms 10 Apr 2025 626th GolfingSuccess 🇬🇷 877 142 463ms 15 days ago 630th mousetail 🇳🇱 876 40 66ms 29 Aug 2025 631st GrayJoKing 🇦🇺 876 84 37ms 19 Jun 2022 631st primo-ppcg 🇹🇭 876 84 36ms 29 Jun 2022 633rd Shanethegamer 🇺🇸 875 51 428ms 15 May 2023 634th Grrisly 875 74 4ms 25 Mar 2024 635th JayXon 🇺🇸 875 157 1,772ms 14 Sep 2025 636th rucin93 🇵🇱 874 57 136ms 4 Aug 2024 636th dokutan 874 57 129ms 9 Aug 2024 638th c0d3-4-F00d 🇩🇪 874 61 10ms 6 May 2022 638th jackkav 874 61 10ms 26 Jun 2022 638th TechNolaByte 874 61 10ms 6 Jul 2022 First Prev 561–640 of 3,506 Next Last