The Calendar hole will go live in approximately 13 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 78th Natanaelel 🇸🇪 897 47 50ms 24 Jan 2025 82nd JayXon 🇺🇸 896 77 2ms 9 Jan 2025 82nd GrayJoKing 🇦🇺 896 77 2ms 12 Jul 2025 82nd edsrzf 🇳🇿 896 77 2ms 17 days ago 85th GrayJoKing 🇦🇺 894 47 6ms 23 days ago 86th nwellnhof 🇩🇪 894 52 261ms 1 Sep 2024 87th Babafaba 893 65 350ms 22 Oct 2025 88th JayXon 🇺🇸 893 99 414ms 11 Jul 2025 88th AdrienHache 🇫🇷 893 99 432ms 17 Sep 2025 88th Yax42 🇫🇷 893 99 402ms 8 Oct 2025 91st edsrzf 🇳🇿 892 59 957ms 90 mins ago 92nd firegene 🇮🇪 891 70 12ms 3 Sep 2024 92nd emplv 🇱🇻 891 70 9ms 17 Sep 2024 92nd snoozingnewt 🇨🇦 891 70 12ms 26 days ago 95th JayXon 🇺🇸 890 101 2ms 18 Sep 2024 96th emgordon154 889 70 4,640ms 8 Nov 2024 97th pardouin 🇫🇷 889 99 118ms 1 Sep 2024 97th Natanaelel 🇸🇪 889 99 116ms 1 Sep 2024 97th ovs-code 🇩🇪 889 99 120ms 1 Sep 2024 97th sean-niemann 🇺🇸 889 99 119ms 4 Sep 2024 97th JayXon 🇺🇸 889 99 117ms 6 Sep 2024 97th lynn 889 99 119ms 8 Jan 2025 97th xnor-gate 889 99 119ms 4 Mar 2025 97th Sakisan 🇧🇪 889 99 115ms 22 Apr 2025 97th tobeannouncd 889 99 133ms 25 Apr 2025 97th HPWiz 🇳🇿 889 99 117ms 27 Sep 2025 107th alemelis 886 59 238ms 1 Sep 2024 107th pardouin 🇫🇷 886 59 362ms 2 Sep 2024 107th antimon2 🇯🇵 886 59 381ms 23 Oct 2024 110th nwellnhof 🇩🇪 886 109 472ms 25 Sep 2025 110th JayXon 🇺🇸 886 109 464ms 25 Sep 2025 112th btnlq 885 55 6ms 1 Sep 2024 112th ovs-code 🇩🇪 885 55 15ms 20 Oct 2024 112th sean-niemann 🇺🇸 885 55 7ms 29 Dec 2024 115th Natanaelel 🇸🇪 885 80 9ms 1 Sep 2024 115th MeWhenI 🇻🇦 885 80 8ms 1 Sep 2024 115th helbling 🇨🇭 885 80 9ms 11 Jul 2025 118th nwellnhof 🇩🇪 884 100 421ms 22 Jul 2025 119th ovs-code 🇩🇪 880 25 50ms 1 Sep 2024 120th lifthrasiir 🇰🇷 880 66 345ms 2 Dec 2024 120th snoozingnewt 🇨🇦 880 66 351ms 26 days ago 122nd GrayJoKing 🇦🇺 879 60 12ms 3 Sep 2024 122nd error256 879 60 12ms 3 Sep 2024 122nd edsrzf 🇳🇿 879 60 12ms 17 days ago 125th starfihs 879 71 157ms 5 Sep 2024 125th dokutan 879 71 10ms 13 Sep 2024 125th KatieLG 🇬🇧 879 71 10ms 14 Sep 2024 125th lifthrasiir 🇰🇷 879 71 14ms 20 Nov 2024 125th plcc0 879 71 10ms 6 Mar 2025 125th keelimeguy 🇺🇸 879 71 10ms 17 May 2025 125th albanian-laundromat 879 71 11ms 5 Jun 2025 132nd radarek 🇵🇱 878 52 864ms 10 Sep 2024 133rd xsot 🇸🇬 878 60 886ms 17 hours ago 134th IanUtley 877 78 14ms 1 Sep 2024 134th kops-cg 877 78 14ms 6 Mar 2025 136th JayXon 🇺🇸 876 71 3,940ms 8 Nov 2024 136th pardouin 🇫🇷 876 71 4,777ms 17 Nov 2024 138th sean-niemann 🇺🇸 876 80 6ms 16 Aug 2025 139th JayXon 🇺🇸 876 122 534ms 18 Sep 2024 140th ashtraypettingzoo 🇺🇸 875 29 3ms 1 Sep 2024 140th GolfingSuccess 🇬🇷 875 29 3ms 25 Mar 2025 142nd GolfingSuccess 🇬🇷 875 48 6ms 13 Dec 2024 142nd MeWhenI 🇻🇦 875 48 6ms 31 Dec 2024 144th emplv 🇱🇻 874 81 9ms 16 Sep 2024 144th vlpx 🇫🇮 874 81 9ms 23 Sep 2024 144th lukegustafson 🇺🇸 874 81 9ms 26 May 2025 147th JayXon 🇺🇸 874 91 103ms 10 Sep 2024 148th error256 873 66 77ms 6 Sep 2024 149th JayXon 🇺🇸 873 137 211ms 10 Jul 2025 149th acotis 873 137 225ms 24 Sep 2025 151st sean-niemann 🇺🇸 872 69 127ms 10 May 2025 152nd JayXon 🇺🇸 868 151 251ms 10 Sep 2024 152nd nwellnhof 🇩🇪 868 151 251ms 10 Sep 2024 152nd 0xjac 🇨🇭 868 151 260ms 23 days ago 155th qpwoeirut 867 72 12ms 1 Oct 2025 156th ovs-code 🇩🇪 866 67 495ms 15 Jul 2025 156th albanian-laundromat 866 67 365ms 4 Aug 2025 158th Frowny 865 35 33ms 1 Sep 2024 158th Natanaelel 🇸🇪 865 35 32ms 1 Sep 2024 158th 4hg 🇺🇸 865 35 33ms 5 Sep 2024 First Prev 81–160 of 707 Next Last