The Calendar hole will go live in approximately 43 hours. Why not try and solve it ahead of time?
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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 801st RockOfStone 685 126 2ms 30 Jul 2022 802nd lynn 684 38 39ms 22 Jul 2022 803rd violeta-desantis 684 137 2ms 27 Sep 2023 804th luuumine 🇫🇷 684 176 148ms 24 Nov 2025 805th DialFrost 🇸🇬 683 90 129ms 3 Nov 2024 806th 0e4ef622 683 101 11ms 21 Jun 2022 806th bricknellj 683 101 10ms 22 Jun 2024 808th MeWhenI 🇻🇦 680 81 262ms 28 Jan 2023 809th a6166231 🇨🇳 680 104 9ms 29 May 2025 810th error256 679 66 37ms 8 May 2025 811th inventshah 679 92 406ms 21 Jan 2024 812th MeWhenI 🇻🇦 677 346 12ms 28 Aug 2023 813th gnuvince 676 45 3ms 29 Jun 2025 814th b10011 🇫🇮 676 102 9ms 14 Jan 2023 814th zacjl 676 102 10ms 21 Oct 2023 814th bzijlema 🇳🇱 676 102 9ms 15 Oct 2024 814th moustave 676 102 10ms 25 Jun 2025 814th blaztoma 🇱🇹 676 102 9ms 9 Oct 2025 819th IlkkaTakala 676 162 68ms 1 Dec 2023 820th Shanethegamer 🇺🇸 675 99 90ms 12 Dec 2022 821st fabianrieder 674 114 360ms 6 Apr 2023 822nd alexsave 673 105 9ms 8 Nov 2024 822nd acollett89 673 105 9ms 1 Aug 2025 822nd LordSir101 673 105 9ms 16 Aug 2025 825th bumchen 672 163 61ms 6 Apr 2023 826th jacobly0 🇺🇸 672 193 41ms 18 Sep 2025 827th MeWhenI 🇻🇦 672 199 25ms 2 Oct 2024 828th MeWhenI 🇻🇦 672 246 9ms 30 Nov 2023 829th Shanethegamer 🇺🇸 671 86 4ms 14 Aug 2024 830th janbehrens 🇩🇪 670 103 9ms 23 Jun 2023 830th orthoplex 🇨🇽 670 103 10ms 25 Nov 2023 830th abc7-12 670 103 9ms 26 Jun 2024 830th madex 🇩🇪 670 103 10ms 7 Aug 2025 830th Lv0Sys 🇵🇱 670 103 10ms 23 days ago 830th FortuiteMan 🇫🇷 670 103 11ms 11 days ago 836th heanyang1 670 140 2ms 21 May 2025 837th bac0id 670 159 387ms 26 Sep 2023 838th stefangimmillaro 669 67 40ms 26 Dec 2024 839th janbehrens 🇩🇪 668 115 329ms 23 Jun 2023 840th SirBogman 🇺🇸 667 39 40ms 4 Oct 2022 841st SirBogman 🇺🇸 667 59 34ms 8 Sep 2022 842nd zakariamouhid 667 106 9ms 14 May 2023 843rd Schmitt-Very-Cool 666 160 453ms 30 Sep 2025 844th Anonymousellama21 665 141 2ms 14 Apr 2022 845th SirBogman 🇺🇸 665 150 38ms 4 Dec 2022 846th swbbl 664 83 263ms 5 Feb 2022 846th Feniske 🇫🇷 664 83 277ms 8 Aug 2022 848th varhammer 🇷🇺 664 152 7ms 7 Nov 2024 849th msbranicky 664 165 60ms 20 Aug 2023 850th VictorFordham 663 104 10ms 20 Feb 2023 850th Alex-x90 🇺🇸 663 104 9ms 3 Aug 2023 850th mathisfun271 663 104 10ms 5 Feb 2024 850th EnTerr 663 104 9ms 8 Sep 2024 850th KasperKivimaeki 🇫🇮 663 104 10ms 11 Jul 2025 855th roavin 663 116 369ms 23 Jun 2022 855th hamhub7 663 116 333ms 9 Aug 2022 855th bac0id 663 116 386ms 22 Sep 2023 855th CaedenHarper 🇨🇦 663 116 355ms 16 Oct 2025 859th NewDefectus 🇮🇱 661 46 2ms 14 Jan 2022 860th BloodStormKnight 661 107 9ms 15 Oct 2022 860th LukeBridges 🇬🇧 661 107 11ms 8 Nov 2022 860th hacker112 🇸🇪 661 107 9ms 24 Jun 2024 863rd akamayu-ouo 🇹🇼 660 142 1ms 8 Jul 2024 864th Herbert00709 🇵🇱 660 166 65ms 5 Apr 2024 865th akshatj27 🇦🇶 659 68 38ms 10 Jan 2022 865th Haksell 🇦🇶 659 68 42ms 23 Feb 2023 867th DialFrost 🇸🇬 659 117 93ms 18 Jun 2024 868th jhpaques 🇫🇷 659 131 2ms 13 Dec 2022 869th madex 🇩🇪 658 183 154ms 7 Aug 2025 870th Lv0Sys 🇵🇱 658 197 41ms 16 days ago 871st Bonjour27891 🇻🇳 657 105 18ms 15 Jul 2022 871st stefangimmillaro 657 105 10ms 26 Dec 2022 871st betaveros 657 105 10ms 1 Jan 2023 871st 5cw 🇺🇸 657 105 9ms 3 May 2023 871st minhtrancccp 657 105 9ms 26 Sep 2023 871st Emutis 🇱🇹 657 105 9ms 4 Feb 2025 877th DialFrost 🇸🇬 657 116 9ms 12 Dec 2024 878th The-Wolfson 657 157 106ms 16 Dec 2024 879th Re-Adventures 🇮🇳 656 143 2ms 7 Feb 2022 879th DrPiranoid 656 143 2ms 21 Oct 2022 First Prev 801–880 of 1,558 Next Last