The Calendar hole will go live in approximately 5 days. Why not try and solve it ahead of time?
τ 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 639th DrPiranoid 628 90 14ms 26 Mar 2023 639th fourth-bit 628 90 15ms 23 Jun 2023 639th BREMAUCY 🇫🇷 628 90 14ms 29 Apr 2024 639th qpwoeirut 628 90 25ms 2 Oct 2025 645th emgordon154 628 210 3,568ms 7 Sep 2024 646th stefangimmillaro 627 160 43ms 26 Apr 2025 647th CatsAreFluffy 626 104 215ms 14 Dec 2022 648th GalladeGuy 🇺🇸 625 180 67ms 25 May 2020 648th Waffle3z 625 180 582ms 8 Apr 2022 650th stefangimmillaro 624 214 195ms 21 Oct 2023 651st rambox11 623 161 7ms 12 Mar 2019 652nd tatzyr 🇯🇵 622 65 44ms 27 Apr 2021 652nd olleicua 🇺🇸 622 65 46ms 13 Mar 2024 652nd Yewzir 🇧🇪 622 65 44ms 8 hours ago 655th Natanaelel 🇸🇪 621 62 1,030ms 21 Apr 2025 656th cure-honey 🇯🇵 619 231 267ms 25 Jun 2021 657th Bonjour27891 🇻🇳 614 92 23ms 2 May 2022 657th CatsAreFluffy 614 92 27ms 7 Dec 2022 659th KatieLG 🇬🇧 614 97 10ms 5 Oct 2025 660th emgordon154 614 110 44ms 10 Dec 2024 661st blaztoma 🇱🇹 613 66 43ms 20 hours ago 662nd alphafalfa 611 63 3,277ms 19 Dec 2024 663rd MeWhenI 🇻🇦 608 165 53ms 29 Apr 2025 664th MeWhenI 🇻🇦 606 219 115ms 28 Jul 2023 665th Bubbler-4 604 96 2,448ms 25 Jan 2022 666th bendiscz 604 237 279ms 20 Apr 2020 667th aksyristos 603 67 46ms 3 Feb 2023 667th Lv0Sys 🇵🇱 603 67 45ms 6 Jun 2025 669th janAkali 🇷🇺 603 218 431ms 28 Jun 2025 670th Yewzir 🇧🇪 601 94 16ms 27 May 2023 670th ImpressedByRocks 601 94 908ms 22 May 2025 672nd BREMAUCY 🇫🇷 601 163 381ms 29 Jul 2025 673rd MeWhenI 🇻🇦 600 167 3ms 1 Aug 2023 674th MeWhenI 🇻🇦 600 394 838ms 29 Aug 2023 675th snoozingnewt 🇨🇦 598 79 736ms 21 Nov 2025 676th BREMAUCY 🇫🇷 598 90 409ms 19 days ago 677th stefangabos 🇷🇴 596 100 10ms 26 Aug 2022 678th annaproxy 595 68 47ms 5 Nov 2022 679th quimey 595 95 87ms 17 Mar 2023 679th roupiq 🇵🇱 595 95 38ms 18 Apr 2024 681st cure-honey 🇯🇵 589 227 926ms 7 Jul 2021 682nd duckyluuk 🇳🇱 586 119 3,271ms 29 Oct 2024 683rd Mabeloid 🇳🇴 586 236 118ms 26 Oct 2025 684th CatsAreFluffy 585 92 484ms 15 Jan 2024 685th AlephSquirrel 584 46 54ms 10 Feb 2023 686th Thonoton 584 65 204ms 24 Feb 2023 686th Natanaelel 🇸🇪 584 65 232ms 16 Jul 2023 688th Bonjour27891 🇻🇳 584 102 10ms 12 Mar 2022 689th snoozingnewt 🇨🇦 584 229 154ms 21 Nov 2025 690th dokutan 584 237 119ms 11 Jan 2024 691st kmathis22 583 204 488ms 18 days ago 692nd Yewzir 🇧🇪 582 246 269ms 3 Jan 2024 693rd unfinishedprogram 578 103 10ms 21 Feb 2024 694th flawr 577 113 752ms 2 Jan 2019 695th dokutan 577 248 290ms 4 Jan 2024 696th KatieLG 🇬🇧 576 98 155ms 11 Dec 2022 696th cingulataluke 576 98 15ms 26 Aug 2023 698th dan-simon 575 67 270ms 29 Dec 2017 699th MeWhenI 🇻🇦 574 167 475ms 13 Oct 2023 700th Yewzir 🇧🇪 573 94 424ms 15 Jan 2024 701st boxjelly 573 175 4ms 7 Feb 2021 702nd 4hg 🇺🇸 572 47 60ms 22 Jul 2022 703rd MeWhenI 🇻🇦 572 230 409ms 15 Nov 2022 704th fisxoj 571 86 19ms 28 Apr 2018 705th MeWhenI 🇻🇦 570 61 12ms 15 Feb 2025 706th janbehrens 🇩🇪 570 88 229ms 3 Dec 2023 707th yokasuretsu 569 71 45ms 15 Apr 2018 707th Irratix 🇳🇱 569 71 69ms 27 Jun 2022 709th tomh1012 567 105 10ms 13 Oct 2020 709th Yax42 🇫🇷 567 105 9ms 5 Sep 2025 711th aksyristos 566 67 170ms 23 Jul 2023 712th dokutan 566 236 89ms 23 Jul 2025 713th bac0id 565 100 15ms 26 Sep 2023 714th MeWhenI 🇻🇦 565 149 54ms 12 Nov 2022 715th Shanethegamer 🇺🇸 564 110 958ms 2 Jun 2022 716th leon-w 559 101 54ms 4 Jan 2019 716th Lv0Sys 🇵🇱 559 101 22ms 26 days ago 718th CatsAreFluffy 557 107 15ms 19 Dec 2022 718th goodwyna21 557 107 10ms 27 Jan 2025 720th Yewzir 🇧🇪 554 261 6ms 19 Dec 2024 First Prev 641–720 of 2,246 Next Last