The Calendar hole will go live in approximately 13 days. Why not try and solve it ahead of time?
PalindromemordnilaP 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 400th snoozingnewt 🇨🇦 752 96 109ms 12 days ago 402nd Shanethegamer 🇺🇸 752 117 119ms 1 Sep 2024 403rd DialFrost 🇸🇬 751 225 453ms 20 Jan 2025 404th sciencejiho 750 102 10ms 13 Sep 2024 404th Papushkado 750 102 9ms 10 Nov 2025 404th JOrE20 🇺🇸 750 102 10ms 10 days ago 407th UnderKoen 🇳🇱 750 185 64ms 16 days ago 408th Shanethegamer 🇺🇸 749 122 6ms 4 Oct 2024 409th error256 748 226 432ms 28 Mar 2025 410th Shanethegamer 🇺🇸 745 95 9ms 1 Sep 2024 410th HumanoidCPU 745 95 9ms 29 Oct 2024 412th julian-hoelz 743 103 10ms 16 Sep 2024 412th StefanHabel 🇨🇦 743 103 97ms 22 Mar 2025 414th Mikey-Beep 🇬🇧 743 119 397ms 2 Sep 2024 415th stefangimmillaro 739 169 44ms 3 Sep 2024 416th Shanethegamer 🇺🇸 737 71 349ms 1 Sep 2024 416th MarcMush 🇫🇷 737 71 692ms 16 Sep 2024 418th pardouin 🇫🇷 736 87 85ms 3 Sep 2024 419th ComputerKWasTaken 🇺🇸 736 104 10ms 2 Sep 2024 419th elgan65536 736 104 9ms 23 Sep 2024 419th NickTheEASDude 🇺🇸 736 104 10ms 7 Oct 2025 422nd FlyingPenguin223 734 94 2ms 18 Sep 2024 423rd MostParsingVex 734 164 77ms 6 Jan 2025 424th GolfingSuccess 🇬🇷 733 30 54ms 1 Sep 2024 424th MeWhenI 🇻🇦 733 30 67ms 8 Jun 2025 424th CaedenHarper 🇨🇦 733 30 45ms 16 days ago 427th snoozingnewt 🇨🇦 731 110 102ms 25 days ago 428th targrik 730 97 9ms 8 Feb 2025 429th error256 730 121 377ms 24 Sep 2024 430th albanian-laundromat 728 232 446ms 15 Oct 2025 431st bitsandbeyond 🇳🇱 726 64 281ms 17 days ago 432nd Shanethegamer 🇺🇸 726 95 2ms 2 Sep 2024 433rd emgordon154 725 63 854ms 18 Nov 2024 434th CutSandstone 722 106 13ms 21 Dec 2024 435th GrayJoKing 🇦🇺 720 86 137ms 2 Sep 2024 436th Shanethegamer 🇺🇸 720 128 377ms 1 Sep 2024 437th dokutan 719 124 3ms 5 Sep 2024 438th Kacarott 🇦🇺 717 132 3ms 4 Sep 2024 439th kg583 🇺🇸 716 106 6ms 26 Sep 2025 440th galloj 🇨🇿 715 107 10ms 4 Sep 2024 440th FlorianCassayre 🇫🇷 715 107 12ms 9 Sep 2024 440th jared-hughes 715 107 10ms 10 Sep 2024 440th nstearns96 🇬🇧 715 107 10ms 13 Nov 2024 440th rchalamala 715 107 10ms 2 Jan 2025 440th brochmann 🇸🇪 715 107 10ms 16 Oct 2025 446th dokutan 713 75 731ms 29 Aug 2025 447th snyderek 🇺🇸 712 150 72ms 15 Sep 2024 448th alexsave 708 100 9ms 22 Sep 2024 449th JesseNoEyes 🇺🇸 708 108 9ms 30 Sep 2024 450th JDiLenarda 🇫🇷 708 170 1,314ms 3 Sep 2024 451st HumanoidCPU 704 90 412ms 2 Sep 2024 452nd adriweb 🇫🇷 704 98 1ms 4 Sep 2024 452nd sean-niemann 🇺🇸 704 98 2ms 5 Sep 2024 452nd dokutan 704 98 2ms 14 Sep 2024 455th Shanethegamer 🇺🇸 704 114 102ms 2 Sep 2024 456th MeWhenI 🇻🇦 703 88 137ms 1 Sep 2024 456th error256 703 88 135ms 10 Sep 2024 458th Mabeloid 🇳🇴 702 109 10ms 1 Sep 2024 458th MassimoParisi 702 109 11ms 18 Sep 2024 458th klixel 🇨🇦 702 109 10ms 21 Sep 2024 458th NotNoper 702 109 9ms 29 Oct 2024 458th za3k 702 109 11ms 15 Jul 2025 458th RaBa21 🇭🇺 702 109 11ms 18 Jul 2025 458th zgialor-lab 702 109 11ms 22 hours ago 465th ovs-code 🇩🇪 702 128 2ms 1 Sep 2024 466th emgordon154 701 101 9ms 1 Sep 2024 467th CaedenHarper 🇨🇦 701 187 256ms 8 Nov 2025 468th frosster 697 99 2ms 21 Mar 2025 469th sean-niemann 🇺🇸 697 114 108ms 7 Sep 2024 470th KatieLG 🇬🇧 696 91 455ms 1 Sep 2024 471st elgan65536 695 172 194ms 23 Sep 2024 472nd MostParsingVex 694 154 1,857ms 15 Sep 2024 473rd sean-niemann 🇺🇸 692 107 2ms 23 Aug 2025 474th stefangimmillaro 691 90 4,548ms 14 Nov 2024 475th aksyristos 689 111 11ms 1 Sep 2024 475th wh3n3v3r 🇨🇿 689 111 10ms 11 Nov 2024 475th AstroOrbis 689 111 10ms 30 Jun 2025 478th Shanethegamer 🇺🇸 689 206 30ms 4 Sep 2024 479th JunkIce 688 92 718ms 3 Dec 2024 480th GolfingSuccess 🇬🇷 686 131 2ms 1 Sep 2024 First Prev 401–480 of 710 Next Last