The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 3 days. Why not try and solve them ahead of time?
Reverse Polish Notation 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 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 Bytes Time Submitted 239th commandz0 🇺🇸 836 124 17ms 23 Mar 2025 239th andrewjc2000 836 124 19ms 14 Jan 2026 243rd HPWiz 🇳🇿 835 40 1,032ms 10 Jan 2026 244th dvargas46 🇺🇸 835 72 53ms 21 Dec 2022 245th stefangimmillaro 835 98 1,285ms 10 Dec 2024 246th MeWhenI 🇻🇦 835 164 461ms 19 Jun 2025 247th Argeento 🇵🇱 834 88 12ms 13 Feb 2022 247th coreynash 834 88 11ms 15 Feb 2024 249th Bubbler-4 833 69 34ms 21 Feb 2022 249th ovs-code 🇩🇪 833 69 34ms 1 Mar 2025 251st btnlq 832 173 2ms 24 Sep 2022 252nd Shanethegamer 🇺🇸 832 190 33ms 10 Feb 2026 252nd Steffan153 🇫🇮 832 190 32ms 23 days ago 254th emgordon154 831 162 2,728ms 30 Jan 2025 255th shinh 830 59 40ms 21 Jun 2022 255th tatzyr 🇯🇵 830 59 38ms 24 Mar 2025 255th lacrosse 830 59 39ms 13 Dec 2025 258th acotis 830 225 241ms 10 Feb 2026 259th Natanaelel 🇸🇪 829 49 7ms 10 Feb 2026 260th GrayJoKing 🇦🇺 829 118 8ms 21 Aug 2024 261st RYNO8 829 125 16ms 16 Aug 2022 261st duckyluuk 🇳🇱 829 125 42ms 23 Feb 2024 263rd btnlq 827 76 2ms 7 Nov 2022 264th Steffan153 🇫🇮 827 99 1,283ms 4 May 2023 265th Z-snails 827 160 141ms 28 Feb 2023 265th Jeremy-Stafford 827 160 146ms 28 Feb 2023 267th Natanaelel 🇸🇪 826 58 1,205ms 4 hours ago 268th Steffan153 🇫🇮 826 77 1,779ms 17 Feb 2026 269th AdrienHache 🇫🇷 826 80 48ms 29 Nov 2024 269th lyphyser 826 80 54ms 5 Jan 2025 271st sisyphus-ppcg 🇦🇺 826 101 5ms 14 Feb 2022 272nd jkelly467 826 163 2,973ms 1 Dec 2025 273rd primo-ppcg 🇹🇭 825 125 6ms 31 Jan 2023 274th snyderek 🇺🇸 825 170 62ms 1 Dec 2024 275th saito-ta 🇯🇵 824 73 256ms 25 Jan 2023 276th ScottHamper 824 89 14ms 18 Feb 2022 276th Shanethegamer 🇺🇸 824 89 12ms 14 Mar 2025 278th edsrzf 🇳🇿 824 99 7ms 17 Jan 2025 279th sean-niemann 🇺🇸 824 100 456ms 6 Jun 2025 280th ovs-code 🇩🇪 823 113 129ms 2 Jul 2025 281st Shanethegamer 🇺🇸 822 122 8ms 12 Apr 2024 282nd dzshn 822 126 15ms 15 Aug 2022 282nd stefangimmillaro 822 126 14ms 10 Nov 2023 282nd fgrosshans 🇫🇷 822 126 13ms 17 Jul 2024 282nd NickTheEASDude 🇺🇸 822 126 21ms 21 Aug 2024 282nd Pyroan 822 126 15ms 13 Mar 2025 282nd 051 🇸🇬 822 126 47ms 8 Jan 2026 288th sean-niemann 🇺🇸 822 127 3ms 8 Jan 2025 288th Steffan153 🇫🇮 822 127 2ms 13 Feb 2026 290th Steffan153 🇫🇮 822 135 108ms 4 May 2023 291st strout 822 161 149ms 15 Dec 2023 292nd Shanethegamer 🇺🇸 821 158 1,453ms 26 Oct 2023 293rd tomtheisen 🇺🇸 820 167 429ms 15 Nov 2022 294th m-tkach 🇺🇦 820 226 5ms 12 Feb 2025 295th lynn 819 228 227ms 6 Jul 2024 296th Shanethegamer 🇺🇸 816 60 37ms 12 Apr 2024 296th snoozingnewt 🇨🇦 816 60 39ms 12 Feb 2026 298th primo-ppcg 🇹🇭 816 100 7ms 21 Aug 2023 299th m-tkach 🇺🇦 816 101 465ms 21 Jan 2024 299th pardouin 🇫🇷 816 101 418ms 23 Jun 2024 301st MaxElf999 816 127 16ms 10 Nov 2022 301st DrakeSeteraO 816 127 24ms 28 Oct 2025 303rd rucin93 🇵🇱 816 128 2ms 12 Jun 2025 304th NewDefectus 🇮🇱 815 90 13ms 12 Feb 2022 304th didion0 🇺🇸 815 90 11ms 17 Feb 2022 304th uttumuttu 🇫🇮 815 90 13ms 5 Mar 2022 304th thisishowmymindworks 🇳🇴 815 90 10ms 24 Jun 2024 308th ovs-code 🇩🇪 815 120 5ms 24 days ago 309th Shanethegamer 🇺🇸 815 134 93ms 4 Jun 2025 310th edsrzf 🇳🇿 815 157 406ms 3 Oct 2025 311th inventshah 815 172 64ms 29 Mar 2025 312th edsrzf 🇳🇿 815 194 32ms 2 Feb 2026 313th btnlq 814 32 4ms 16 Jul 2023 313th MeWhenI 🇻🇦 814 32 4ms 16 Jul 2023 313th Steffan153 🇫🇮 814 32 4ms 16 Jul 2023 313th ovs-code 🇩🇪 814 32 3ms 16 Jul 2023 313th fuzzylojik-golf 🇺🇸 814 32 4ms 18 Sep 2025 318th blaztoma 🇱🇹 814 148 101ms 22 days ago 318th snoozingnewt 🇨🇦 814 148 100ms 21 days ago 318th DialFrost 🇸🇬 814 148 97ms 21 days ago First Prev 241–320 of 1,191 Next Last