The Calendar hole will go live in approximately 11 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 481st JunkIce 688 92 718ms 3 Dec 2024 482nd GolfingSuccess 🇬🇷 686 131 2ms 1 Sep 2024 483rd kaascevich 685 116 1,645ms 15 Sep 2025 484th emgordon154 682 288 1,927ms 2 Oct 2024 485th DialFrost 🇸🇬 681 62 45ms 30 Jan 2025 486th olleicua 🇺🇸 681 104 9ms 11 Sep 2024 486th charliegaming 681 104 9ms 28 Nov 2024 488th DialFrost 🇸🇬 681 118 93ms 22 Jun 2025 489th MeWhenI 🇻🇦 679 117 113ms 2 Sep 2024 489th stefangimmillaro 679 117 101ms 2 Sep 2024 491st edsrzf 🇳🇿 678 92 5ms 10 Oct 2024 492nd BlankSpruce 676 158 86ms 1 Sep 2024 493rd madex 🇩🇪 676 177 212ms 17 Sep 2024 494th dcgjb 674 69 292ms 11 Sep 2024 495th stefangimmillaro 670 63 52ms 2 Sep 2024 495th SirBogman 🇺🇸 670 63 37ms 5 Sep 2024 497th alicethecatwhisperermeow 669 132 395ms 14 Sep 2024 498th madeforlosers 668 106 8ms 23 Oct 2024 499th chunes3 🇺🇸 668 112 68ms 1 Sep 2024 500th DialFrost 🇸🇬 666 76 16ms 1 Aug 2025 501st voytxt 🇨🇿 665 93 134ms 17 Apr 2025 502nd dokutan 662 79 245ms 3 Sep 2024 503rd Maznek 662 107 9ms 8 Oct 2024 503rd dokutan 662 107 9ms 5 Jun 2025 505th DialFrost 🇸🇬 661 181 193ms 12 Apr 2025 505th error256 661 181 175ms 22 May 2025 507th GolfingSuccess 🇬🇷 660 162 538ms 1 Sep 2024 507th ovs-code 🇩🇪 660 162 2,853ms 1 Sep 2024 509th LeoCh01 659 116 9ms 1 Sep 2024 510th NickTheEASDude 🇺🇸 657 105 2ms 7 Oct 2025 511th msbranicky 656 136 3ms 1 Sep 2024 512th msbranicky 655 95 3,872ms 8 Jan 2025 513th Shanethegamer 🇺🇸 655 135 422ms 1 Sep 2024 514th albanian-laundromat 655 189 44ms 14 Sep 2025 515th lukechampine 655 200 255ms 7 Jun 2025 515th jerrandolph 655 200 264ms 21 Sep 2025 517th Shanethegamer 🇺🇸 651 95 141ms 8 Jan 2025 518th AlephSquirrel 650 248 3ms 29 Sep 2024 519th TFeld00 🇩🇰 649 65 53ms 3 Sep 2024 520th ShiraJoseph 🇺🇸 649 109 9ms 22 Sep 2024 521st msbranicky 646 203 257ms 1 Sep 2024 522nd error256 645 106 13ms 18 Apr 2025 523rd Waffle3z 645 107 2ms 2 Oct 2024 524th stefangimmillaro 643 71 819ms 3 Sep 2024 525th mrxz 🇳🇱 643 110 9ms 22 Sep 2024 525th weliveinhell 🇭🇹 643 110 9ms 28 Sep 2024 527th Zhenyu-Bo 643 119 11ms 1 Aug 2025 528th BlankSpruce 642 140 2ms 1 Sep 2024 529th stefangimmillaro 640 151 437ms 6 Oct 2025 530th anter69 🇭🇺 639 66 51ms 25 Oct 2024 531st emgordon154 639 113 112ms 16 days ago 532nd aDwarfNamedUrist 639 138 119ms 4 Sep 2024 533rd SirBogman 🇺🇸 637 73 308ms 23 Jul 2025 534th lhulinsky 637 120 11ms 23 Oct 2024 534th arjunarya1 637 120 10ms 11 Sep 2025 536th stefangimmillaro 636 188 199ms 4 Jun 2025 537th emgordon154 635 40 3ms 20 Nov 2025 538th Shanethegamer 🇺🇸 634 72 861ms 1 Sep 2024 538th anter69 🇭🇺 634 72 858ms 25 Oct 2024 540th Ripick 633 127 392ms 6 Sep 2024 541st KatieLG 🇬🇧 632 112 9ms 1 Sep 2024 541st CaedenHarper 🇨🇦 632 112 10ms 22 Aug 2025 543rd dokutan 632 120 6ms 1 Sep 2024 543rd Shanethegamer 🇺🇸 632 120 6ms 2 Sep 2024 545th olleicua 🇺🇸 630 67 44ms 6 Sep 2024 546th RedzGoose 🇦🇺 627 101 475ms 15 Oct 2024 547th kevinnaviapaiva 627 122 12ms 16 Feb 2025 548th BalaM314 626 113 8ms 4 Feb 2025 549th cthierfelder 🇲🇨 624 193 77ms 5 Sep 2025 550th kmathis22 623 155 356ms 5 days ago 551st SirBogman 🇺🇸 622 59 158ms 23 Jul 2025 552nd DialFrost 🇸🇬 622 111 2ms 22 Nov 2024 553rd eddvrs 622 123 11ms 29 Sep 2024 554th KrausRaus 🇺🇸 621 114 11ms 1 Sep 2024 555th Shanethegamer 🇺🇸 620 68 37ms 1 Sep 2024 555th emgordon154 620 68 38ms 1 Sep 2024 555th rvs314 620 68 40ms 24 Sep 2024 555th tatzyr 🇯🇵 620 68 38ms 10 Oct 2025 559th lifthrasiir 🇰🇷 618 227 46ms 11 Dec 2024 560th yokasuretsu 617 124 11ms 10 Jul 2025 First Prev 481–560 of 712 Next Last