The Calendar hole will go live in approximately 11 days. 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 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 399th dokutan 704 98 2ms 14 Sep 2024 402nd Shanethegamer 🇺🇸 704 114 102ms 2 Sep 2024 403rd ovs-code 🇩🇪 702 128 2ms 1 Sep 2024 404th OllieBoyne 🇬🇧 701 89 10ms 9 Sep 2024 404th davecame 701 89 11ms 17 Sep 2024 404th Bmrl7 701 89 9ms 3 Oct 2024 404th DialFrost 🇸🇬 701 89 10ms 21 Nov 2024 404th CommandLeo 🇮🇹 701 89 10ms 23 days ago 404th KasperKivimaeki 🇫🇮 701 89 10ms 20 days ago 410th CaedenHarper 🇨🇦 701 187 256ms 8 Nov 2025 411th GrayJoKing 🇦🇺 700 86 137ms 2 Sep 2024 411th dokutan 700 86 122ms 15 Jun 2025 413th CaedenHarper 🇨🇦 699 83 487ms 9 Aug 2025 414th MeWhenI 🇻🇦 698 151 43ms 4 Sep 2024 415th frosster 697 99 2ms 21 Mar 2025 416th sean-niemann 🇺🇸 697 114 108ms 7 Sep 2024 417th elgan65536 695 172 194ms 23 Sep 2024 418th mamamia5x 694 102 9ms 12 Sep 2024 419th MostParsingVex 694 154 1,857ms 15 Sep 2024 420th dokutan 693 75 731ms 29 Aug 2025 421st tatzyr 🇯🇵 692 61 37ms 10 Oct 2025 422nd sean-niemann 🇺🇸 692 107 2ms 23 Aug 2025 423rd stefangimmillaro 691 90 4,548ms 14 Nov 2024 424th Shanethegamer 🇺🇸 689 206 30ms 4 Sep 2024 425th BlankSpruce 686 91 9ms 1 Sep 2024 425th ZakkkkAttackkkk 🇵🇭 686 91 10ms 1 Sep 2024 425th BREMAUCY 🇫🇷 686 91 10ms 3 Sep 2024 425th charliegaming 686 91 10ms 7 Sep 2024 425th mbittner20 686 91 10ms 9 Sep 2024 425th neihousaigaai 686 91 9ms 28 Sep 2024 425th Rubiksmath 686 91 11ms 1 Oct 2024 425th jameswmccarty 686 91 10ms 2 Dec 2024 425th croc54 686 91 11ms 12 Jan 2025 425th Pyroan 686 91 11ms 24 Feb 2025 425th WillowWispy 686 91 11ms 21 Mar 2025 425th clayboll99 686 91 11ms 15 Jul 2025 425th blaztoma 🇱🇹 686 91 10ms 21 Sep 2025 425th vhoulbreque 🇫🇷 686 91 10ms 21 Nov 2025 425th FortuiteMan 🇫🇷 686 91 11ms 20 days ago 425th LostSyntax21 🇬🇧 686 91 10ms 19 days ago 425th CaedenHarper 🇨🇦 686 91 30ms 18 days ago 425th Lv0Sys 🇵🇱 686 91 9ms 10 days ago 443rd GolfingSuccess 🇬🇷 686 131 2ms 1 Sep 2024 444th kaascevich 685 116 1,645ms 15 Sep 2025 445th MeWhenI 🇻🇦 684 88 137ms 1 Sep 2024 445th error256 684 88 135ms 10 Sep 2024 447th emgordon154 682 288 1,927ms 2 Oct 2024 448th DialFrost 🇸🇬 681 62 45ms 30 Jan 2025 448th KatieLG 🇬🇧 681 62 38ms 2 Oct 2025 450th olleicua 🇺🇸 681 104 9ms 11 Sep 2024 451st MeWhenI 🇻🇦 679 117 113ms 2 Sep 2024 451st stefangimmillaro 679 117 101ms 2 Sep 2024 453rd fourth-bit 678 92 10ms 4 Sep 2024 453rd bnic24 678 92 10ms 5 Sep 2024 453rd edsrzf 🇳🇿 678 92 5ms 10 Oct 2024 456th BlankSpruce 676 158 86ms 1 Sep 2024 457th madex 🇩🇪 676 177 212ms 17 Sep 2024 458th dokutan 675 156 42ms 1 Sep 2024 459th dcgjb 674 69 292ms 11 Sep 2024 460th dokutan 671 78 192ms 3 Sep 2024 461st adamnielson42 🇺🇸 671 93 9ms 7 Oct 2024 461st smiksky 🇺🇸 671 93 10ms 16 Oct 2024 461st guilhem-roy 🇫🇷 671 93 14ms 31 May 2025 464th stefangimmillaro 670 63 52ms 2 Sep 2024 464th SirBogman 🇺🇸 670 63 37ms 5 Sep 2024 466th alicethecatwhisperermeow 669 132 395ms 14 Sep 2024 467th madeforlosers 668 106 8ms 23 Oct 2024 468th chunes3 🇺🇸 668 112 68ms 1 Sep 2024 469th DialFrost 🇸🇬 666 76 16ms 1 Aug 2025 470th mousetail 🇳🇱 664 94 13ms 1 Sep 2024 470th ljweel 664 94 10ms 12 Sep 2024 472nd Maznek 662 107 9ms 8 Oct 2024 473rd Shanethegamer 🇺🇸 661 91 141ms 5 Sep 2024 474th DialFrost 🇸🇬 661 181 193ms 12 Apr 2025 474th error256 661 181 175ms 22 May 2025 476th GolfingSuccess 🇬🇷 660 162 538ms 1 Sep 2024 476th ovs-code 🇩🇪 660 162 2,853ms 1 Sep 2024 478th dokutan 659 64 51ms 23 Feb 2025 479th msbranicky 657 95 11ms 1 Sep 2024 479th Bulmenisaurus 657 95 12ms 4 Sep 2024 First Prev 401–480 of 710 Next Last