The Calendar hole will go live in approximately 13 days. Why not try and solve it ahead of time?
Leap Years in all languages in bytes. 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 Bytes Time Submitted 623rd ListeriaM 902 47 18ms 24 Aug 2023 623rd bizy-coder 902 47 16ms 2 Feb 2024 623rd BREMAUCY 🇫🇷 902 47 20ms 25 Mar 2024 623rd Bulmenisaurus 902 47 24ms 4 Aug 2024 623rd voytxt 🇨🇿 902 47 15ms 20 Sep 2024 623rd dokutan 902 47 10ms 25 Sep 2024 623rd lifthrasiir 🇰🇷 902 47 15ms 20 Nov 2024 623rd plcc0 902 47 9ms 6 Mar 2025 623rd jipsong 🇩🇪 902 47 9ms 1 Apr 2025 623rd KasperKivimaeki 🇫🇮 902 47 17ms 14 May 2025 623rd keelimeguy 🇺🇸 902 47 19ms 16 May 2025 623rd Flekay 🇩🇪 902 47 20ms 9 Aug 2025 623rd janlelis 902 47 16ms 14 Aug 2025 623rd snoozingnewt 🇨🇦 902 47 16ms 26 Sep 2025 623rd blaztoma 🇱🇹 902 47 21ms 30 Sep 2025 623rd Emutis 🇱🇹 902 47 19ms 25 Oct 2025 623rd CommandLeo 🇮🇹 902 47 18ms 18 days ago 623rd Lv0Sys 🇵🇱 902 47 16ms 15 days ago 659th Steffan153 🇫🇮 902 51 1,233ms 1 Jan 2023 659th neel11235813 902 51 1,279ms 4 Jan 2023 659th MeWhenI 🇻🇦 902 51 1,256ms 8 Jun 2023 659th dokutan 902 51 1,267ms 14 Oct 2024 659th DialFrost 🇸🇬 902 51 1,367ms 9 Mar 2025 659th sean-niemann 🇺🇸 902 51 1,315ms 18 Apr 2025 659th fuzzylojik-golf 🇺🇸 902 51 1,301ms 2 Sep 2025 666th Attero 🇸🇪 902 58 2ms 12 Mar 2020 666th filharmonista 902 58 2ms 13 Mar 2020 666th cywong-amino 🇭🇰 902 58 1ms 30 May 2020 666th nwellnhof 🇩🇪 902 58 2ms 4 Oct 2020 666th primo-ppcg 🇹🇭 902 58 2ms 5 Oct 2020 666th Irratix 🇳🇱 902 58 2ms 9 Oct 2020 666th madex 🇩🇪 902 58 2ms 23 Mar 2021 666th NewDefectus 🇮🇱 902 58 2ms 27 May 2021 666th tsunderu 🇯🇵 902 58 1ms 2 Sep 2021 666th sean-niemann 🇺🇸 902 58 1ms 5 Jan 2022 666th GrayJoKing 🇦🇺 902 58 2ms 9 Feb 2022 666th voytxt 🇨🇿 902 58 2ms 7 Apr 2022 666th emplv 🇱🇻 902 58 1ms 28 Apr 2022 666th prplz 🇦🇺 902 58 2ms 22 May 2022 666th jared-hughes 902 58 2ms 24 Jun 2022 666th MeWhenI 🇻🇦 902 58 1ms 6 Sep 2022 666th Steffan153 🇫🇮 902 58 1ms 26 Dec 2022 666th inventshah 902 58 2ms 26 Jan 2023 666th ovs-code 🇩🇪 902 58 2ms 5 Feb 2023 666th xsot 🇸🇬 902 58 1ms 19 Mar 2023 666th rucin93 🇵🇱 902 58 2ms 21 Jun 2023 666th stefangimmillaro 902 58 2ms 4 Aug 2023 666th ListeriaM 902 58 2ms 24 Aug 2023 666th JohandeRuiter 🇳🇱 902 58 2ms 25 Oct 2023 666th dokutan 902 58 2ms 25 Sep 2024 666th FlyingPenguin223 902 58 1ms 10 Feb 2025 666th kdx2a 902 58 2ms 11 Feb 2025 666th Mukundan314 902 58 1ms 26 Apr 2025 666th fuzzylojik-golf 🇺🇸 902 58 2ms 28 Jun 2025 666th Yax42 🇫🇷 902 58 2ms 9 Oct 2025 666th ApoChagi 902 58 1ms 14 Oct 2025 666th Babafaba 902 58 1ms 15 Oct 2025 666th 09cf 902 58 2ms 22 days ago 699th sean-niemann 🇺🇸 901 38 68ms 14 Sep 2023 699th blaztoma 🇱🇹 901 38 82ms 2 Nov 2025 701st arjanadriaanse 🇳🇱 901 52 121ms 1 Jan 2022 702nd retrohun 900 46 1ms 16 Jun 2024 703rd Shanethegamer 🇺🇸 900 79 72ms 12 Jan 2022 703rd Yewzir 🇧🇪 900 79 79ms 9 Dec 2023 703rd oceko 900 79 62ms 19 Feb 2024 703rd CaedenHarper 🇨🇦 900 79 62ms 1 Feb 2025 703rd yanjs 900 79 487ms 10 Jul 2025 703rd AutumnWind75 900 79 459ms 8 days ago 709th MeWhenI 🇻🇦 899 54 96ms 15 Oct 2022 709th Yax42 🇫🇷 899 54 96ms 5 Oct 2025 711th AlephSquirrel 899 60 5ms 13 Mar 2023 711th Lydxn 🇨🇦 899 60 15ms 31 Jan 2025 711th edsrzf 🇳🇿 899 60 14ms 3 days ago 714th JayXon 🇺🇸 899 69 25ms 17 Apr 2022 715th billings7 🇬🇧 898 63 320ms 21 Nov 2021 715th ChristophHornung 898 63 315ms 21 Nov 2021 715th KatieLG 🇬🇧 898 63 347ms 17 Oct 2022 718th nwellnhof 🇩🇪 896 89 271ms 3 Sep 2020 718th MeWhenI 🇻🇦 896 89 274ms 10 Oct 2022 718th DialFrost 🇸🇬 896 89 246ms 8 Nov 2023 First Prev 641–720 of 4,757 Next Last