The Calendar hole will go live in approximately 3 hours. Why not try and solve it ahead of time?
PalindromemordnilaP 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 ArkScript 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 ArkScript 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 560th elgan65536 600 104 9ms 23 Sep 2024 560th NickTheEASDude 🇺🇸 600 104 10ms 7 Oct 2025 563rd Shanethegamer 🇺🇸 600 134 412ms 1 Sep 2024 564th inventshah 599 150 2ms 1 Sep 2024 565th Shanethegamer 🇺🇸 595 177 45ms 4 Sep 2024 566th mousetail 🇳🇱 594 105 5ms 3 Sep 2024 567th CaedenHarper 🇨🇦 594 149 392ms 16 Oct 2025 568th BREMAUCY 🇫🇷 594 316 12ms 7 Aug 2025 569th KatieLG 🇬🇧 593 77 790ms 1 Sep 2024 570th h3ra993huskp 🇯🇵 592 163 687ms 30 Nov 2025 571st CutSandstone 589 106 13ms 21 Dec 2024 572nd KatieLG 🇬🇧 589 135 94ms 21 Nov 2025 573rd luuumine 🇫🇷 586 204 194ms 18 Nov 2025 574th Shanethegamer 🇺🇸 584 120 6ms 2 Sep 2024 575th cbrt-x 584 151 121ms 11 Sep 2024 576th DialFrost 🇸🇬 583 107 6ms 1 Sep 2024 576th galloj 🇨🇿 583 107 10ms 4 Sep 2024 576th jared-hughes 583 107 10ms 10 Sep 2024 576th nstearns96 🇬🇧 583 107 10ms 13 Nov 2024 576th brochmann 🇸🇪 583 107 10ms 16 Oct 2025 581st Upload-and-View 🇺🇦 580 119 2ms 23 Jul 2025 582nd GeorgeStechman 🇬🇧 580 122 12ms 5 Nov 2024 582nd gigaprofisi 🇺🇸 580 122 10ms 10 Aug 2025 584th snoozingnewt 🇨🇦 580 226 251ms 1 Sep 2024 585th JesseNoEyes 🇺🇸 578 108 9ms 30 Sep 2024 586th JohandeRuiter 🇳🇱 576 156 2ms 2 Sep 2024 587th RedzGoose 🇦🇺 575 101 552ms 15 Oct 2024 588th xyangst 575 123 11ms 15 Oct 2024 589th Mabeloid 🇳🇴 573 109 10ms 1 Sep 2024 589th MassimoParisi 573 109 11ms 18 Sep 2024 589th klixel 🇨🇦 573 109 10ms 21 Sep 2024 589th NotNoper 573 109 9ms 29 Oct 2024 589th za3k 573 109 11ms 15 Jul 2025 594th vhoulbreque 🇫🇷 573 146 196ms 11 Nov 2025 595th TeodorDyakov 🇧🇬 565 159 2ms 6 Sep 2025 596th TheZwierzLF 🇵🇱 563 75 36ms 4 days ago 597th aksyristos 562 111 11ms 1 Sep 2024 597th AstroOrbis 562 111 10ms 30 Jun 2025 599th tomh1012 562 126 12ms 18 Sep 2025 600th MostParsingVex 562 160 33ms 30 Sep 2024 601st dokutan 561 132 3ms 1 Sep 2024 602nd emgordon154 559 138 11ms 1 Jan 2025 603rd JOrE20 🇺🇸 557 127 12ms 8 days ago 604th RedzGoose 🇦🇺 553 145 114ms 9 Sep 2024 605th msbranicky 548 135 3ms 1 Sep 2024 606th HumanoidCPU 547 110 143ms 22 Nov 2025 607th Yewzir 🇧🇪 543 115 11ms 1 Dec 2025 608th DialFrost 🇸🇬 539 76 16ms 1 Aug 2025 609th KatieLG 🇬🇧 539 128 2ms 2 Oct 2025 610th dokutan 539 155 242ms 1 Sep 2024 611th Shanethegamer 🇺🇸 538 107 91ms 1 Sep 2024 612th LeoCh01 538 116 9ms 1 Sep 2024 613th Shanethegamer 🇺🇸 536 91 25ms 1 Sep 2024 614th snoozingnewt 🇨🇦 535 79 38ms 12 Oct 2025 615th Mabeloid 🇳🇴 533 109 507ms 17 Sep 2024 616th albanian-laundromat 533 352 11ms 18 Sep 2025 617th trijin 529 118 6ms 5 Oct 2024 618th Shanethegamer 🇺🇸 528 183 452ms 24 Sep 2025 619th emgordon154 527 133 15ms 16 Dec 2024 620th Zhenyu-Bo 524 119 11ms 1 Aug 2025 621st tomh1012 524 169 395ms 17 Sep 2025 622nd lhulinsky 520 120 11ms 23 Oct 2024 622nd arjunarya1 520 120 10ms 11 Sep 2025 624th ravnskjaer 🇩🇰 519 186 344ms 16 days ago 625th error256 515 134 2ms 24 Sep 2024 626th CaedenHarper 🇨🇦 514 188 438ms 3 Oct 2025 627th kevinnaviapaiva 512 122 12ms 16 Feb 2025 628th Shanethegamer 🇺🇸 512 141 105ms 27 days ago 629th eddvrs 507 123 11ms 29 Sep 2024 630th Yewzir 🇧🇪 505 115 423ms 1 Dec 2025 631st madex 🇩🇪 503 84 36ms 1 Sep 2024 632nd yokasuretsu 503 124 11ms 10 Jul 2025 632nd hamilton-bonds 503 124 10ms 24 Jul 2025 634th dbut2 🇦🇺 502 261 254ms 3 Sep 2024 635th LukeBridges 🇬🇧 498 142 10ms 3 Sep 2024 636th snoozingnewt 🇨🇦 497 160 101ms 1 Sep 2024 637th MeWhenI 🇻🇦 497 181 2ms 13 Jun 2025 638th nhausspiegel 495 126 10ms 13 Sep 2024 639th matsagad 491 127 10ms 16 Jan 2025 640th madex 🇩🇪 491 183 2ms 2 Sep 2024 First Prev 561–640 of 716 Next Last