The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 31 hours. Why not try and solve them ahead of time?
Reverse Polish Notation 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 Calendar Card Number Validation Catalan Numbers Catalan’s Constant Christmas Trees Collatz Continued Fractions 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 Multitap Input 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 Alphabetic Numbers Apéry’s Constant Binary Lambda Calculus Connect Four Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Rectangle Fill Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial All Languages ><> ALGOL 68 ArkScript 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 APL Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight Lily Luau Odin Picat Qore Racket Rebol Rexx Scala Squirrel Stax Uiua Umka Vala Vyxal Bytes Chars Scoring Bytes Chars Language All ><> ALGOL 68 ArkScript 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 APL Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight Lily 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 Calendar Card Number Validation Catalan Numbers Catalan’s Constant Christmas Trees Collatz Continued Fractions 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 Multitap Input 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 Alphabetic Numbers Apéry’s Constant Binary Lambda Calculus Connect Four Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Rectangle Fill Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial # Golfer Points Chars Time Submitted 299th duckyluuk 🇳🇱 800 5 49ms 4 Sep 2024 299th gigaprofisi 🇺🇸 800 5 50ms 10 Mar 2025 299th albanian-laundromat 800 5 51ms 20 Aug 2025 299th blaztoma 🇱🇹 800 5 48ms 8 Jan 2026 299th TheZwierzLF 🇵🇱 800 5 53ms 9 Jan 2026 299th JOrE20 800 5 47ms 10 Feb 2026 327th emgordon154 800 83 451ms 29 Sep 2025 328th P-Quentin 🇫🇷 800 94 16ms 5 Aug 2022 328th SB-945 800 94 18ms 11 Jan 2024 330th edsrzf 🇳🇿 800 142 46ms 16 Aug 2025 331st Steffan153 🇫🇮 800 181 72ms 3 days ago 332nd primo-ppcg 🇹🇭 800 236 26ms 25 Jun 2022 333rd aadenboy 🇺🇸 799 123 3ms 17 Dec 2025 334th tayloia 🇬🇧 798 92 14ms 10 Jan 2023 334th voytxt 🇨🇿 798 92 12ms 28 Dec 2023 334th olleicua 🇺🇸 798 92 11ms 12 Feb 2024 334th targrik 798 92 11ms 3 Apr 2025 334th fuzzylojik-golf 🇺🇸 798 92 12ms 19 Jul 2025 334th edsrzf 🇳🇿 798 92 11ms 8 days ago 340th nwellnhof 🇩🇪 798 146 2ms 16 Feb 2022 341st MeWhenI 🇻🇦 798 229 41ms 2 Jul 2023 342nd GrayJoKing 🇦🇺 796 40 63ms 13 Sep 2023 342nd chunes3 🇺🇸 796 40 70ms 13 Sep 2023 342nd Bubbler-4 796 40 69ms 13 Sep 2023 342nd sisyphus-ppcg 🇦🇺 796 40 64ms 13 Sep 2023 342nd gifti258 796 40 69ms 13 Sep 2023 342nd ovs-code 🇩🇪 796 40 60ms 13 Sep 2023 342nd GolfingSuccess 🇬🇷 796 40 63ms 15 Sep 2023 342nd Steffan153 🇫🇮 796 40 71ms 17 Sep 2023 342nd 4hg 🇺🇸 796 40 69ms 18 Sep 2023 342nd primo-ppcg 🇹🇭 796 40 67ms 19 Sep 2023 342nd MeWhenI 🇻🇦 796 40 71ms 6 Nov 2023 342nd edsrzf 🇳🇿 796 40 64ms 25 Sep 2024 342nd pardouin 🇫🇷 796 40 65ms 25 Sep 2024 342nd sean-niemann 🇺🇸 796 40 65ms 9 Apr 2025 342nd DialFrost 🇸🇬 796 40 64ms 9 Apr 2025 342nd fuzzylojik-golf 🇺🇸 796 40 62ms 17 Sep 2025 342nd JayXon 🇺🇸 796 40 65ms 4 Nov 2025 359th JRaspass 🇬🇧 796 51 7ms 12 Feb 2022 359th akshatj27 🇦🇶 796 51 5ms 12 Feb 2022 359th NewDefectus 🇮🇱 796 51 6ms 12 Feb 2022 359th ovs-code 🇩🇪 796 51 8ms 4 May 2023 363rd ovs-code 🇩🇪 796 312 1,468ms 1 Feb 2025 364th Sakisan 🇧🇪 795 42 1,032ms 29 Dec 2025 365th pardouin 🇫🇷 795 103 2,699ms 9 Aug 2025 366th verticallity 795 235 188ms 5 Apr 2022 367th primo-ppcg 🇹🇭 793 189 39ms 6 Jul 2022 368th nwellnhof 🇩🇪 792 73 420ms 3 Jun 2022 369th Waffle3z 792 124 3ms 8 Apr 2022 370th andersk 🇺🇸 792 236 194ms 1 Nov 2022 370th funnsam 🇭🇰 792 236 254ms 23 Oct 2023 372nd jared-hughes 792 261 9ms 8 Jul 2024 373rd Irratix 🇳🇱 791 95 13ms 7 May 2022 373rd JunkIce 791 95 35ms 2 Dec 2024 373rd luuumine 🇫🇷 791 95 15ms 7 Oct 2025 376th GolfingSuccess 🇬🇷 791 132 4ms 29 Jan 2024 377th GrayJoKing 🇦🇺 791 200 35ms 17 Jan 2023 378th GolfingSuccess 🇬🇷 791 314 1,414ms 3 Feb 2025 379th prplz 🇦🇺 789 93 11ms 14 Feb 2022 379th primo-ppcg 🇹🇭 789 93 14ms 16 Feb 2022 379th dzshn 789 93 12ms 24 Aug 2022 379th eranws 789 93 13ms 13 Oct 2022 379th biocommando 🇫🇮 789 93 12ms 13 Mar 2024 379th BalaM314 789 93 14ms 7 Feb 2025 379th Andrey-Plotnikov 789 93 11ms 25 Jun 2025 379th KatieLG 🇬🇧 789 93 12ms 5 Oct 2025 387th KasperKivimaeki 🇫🇮 788 178 446ms 8 Dec 2025 388th mousetail 🇳🇱 788 237 189ms 16 May 2024 389th adriweb 🇫🇷 786 125 11ms 12 Oct 2023 390th 2bular 785 44 3ms 21 Jun 2025 391st btnlq 785 131 25ms 30 Mar 2022 392nd GrayJoKing 🇦🇺 784 104 6ms 31 Aug 2023 393rd KatieLG 🇬🇧 783 96 92ms 29 Jul 2024 394th duckyluuk 🇳🇱 783 143 10ms 26 Feb 2025 395th MostParsingVex 782 149 1ms 3 Jan 2025 396th KrausRaus 🇺🇸 781 94 11ms 13 Feb 2022 396th SirBogman 🇺🇸 781 94 14ms 7 May 2022 396th iliazeus 781 94 25ms 4 Sep 2022 396th Natanaelel 🇸🇪 781 94 13ms 9 Dec 2023 396th LukeBridges 🇬🇧 781 94 15ms 2 Oct 2024 First Prev 321–400 of 1,186 Next Last