The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 7 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 154th Lv0Sys 🇵🇱 864 120 20ms 24 days ago 162nd nwellnhof 🇩🇪 863 47 7ms 14 Feb 2022 163rd dcgjb 863 67 532ms 23 Feb 2024 164th nathanadams 🇳🇿 863 85 11ms 15 Apr 2023 165th ScottHamper 862 159 389ms 21 Feb 2022 166th JayXon 🇺🇸 862 212 298ms 21 Feb 2022 167th GrayJoKing 🇦🇺 861 33 4ms 8 May 2022 168th JayXon 🇺🇸 861 95 384ms 19 May 2022 169th kumavale 861 217 224ms 28 Oct 2025 170th stefangimmillaro 859 57 38ms 18 Feb 2022 171st KasperKivimaeki 🇫🇮 857 137 2ms 24 Jul 2025 172nd MeWhenI 🇻🇦 857 186 479ms 7 Nov 2025 173rd primo-ppcg 🇹🇭 856 121 22ms 4 Mar 2022 173rd EnTerr 856 121 24ms 8 Sep 2024 173rd Bulmenisaurus 856 121 12ms 3 Oct 2025 173rd CornerMercury 🇬🇧 856 121 16ms 28 Dec 2025 177th ovs-code 🇩🇪 855 164 461ms 3 Jun 2024 178th Shanethegamer 🇺🇸 854 155 143ms 14 Feb 2022 179th Irratix 🇳🇱 853 86 12ms 13 Feb 2022 179th emplv 🇱🇻 853 86 18ms 16 Feb 2022 179th vlpx 🇫🇮 853 86 12ms 1 Aug 2024 182nd primo-ppcg 🇹🇭 852 98 4ms 16 Feb 2022 183rd Lydxn 🇨🇦 849 97 419ms 16 Jan 2024 184th Shanethegamer 🇺🇸 849 122 17ms 12 Feb 2022 184th ahmetdemirag 🇨🇾 849 122 15ms 15 Jul 2024 186th tobeannouncd 849 156 143ms 9 Jan 2024 187th primo-ppcg 🇹🇭 847 71 5ms 23 Apr 2025 187th frankgraziano 847 71 8ms 23 Apr 2025 189th ChiefChippy2 845 48 6ms 12 Feb 2022 189th GrayJoKing 🇦🇺 845 48 6ms 12 Feb 2022 189th o0lit3 🇺🇸 845 48 6ms 12 Feb 2022 189th Lydxn 🇨🇦 845 48 5ms 13 Feb 2022 189th lynn 845 48 6ms 13 Feb 2022 189th scpchicken 🇵🇼 845 48 6ms 13 Feb 2022 189th Steffan153 🇫🇮 845 48 6ms 3 Dec 2022 189th fuzzylojik-golf 🇺🇸 845 48 6ms 3 Jun 2025 189th xsot 🇸🇬 845 48 8ms 6 Jul 2025 198th janlelis 844 58 67ms 23 Feb 2022 198th SirBogman 🇺🇸 844 58 40ms 10 Jan 2024 200th akshatj27 🇦🇶 843 87 15ms 12 Feb 2022 200th itsh01 843 87 13ms 15 Feb 2022 200th subzey 843 87 10ms 18 Feb 2022 200th emgordon154 843 87 12ms 20 Sep 2024 200th ovs-code 🇩🇪 843 87 11ms 16 Nov 2024 200th lukegustafson 🇺🇸 843 87 11ms 20 days ago 206th antimon2 🇯🇵 843 97 1,137ms 20 Oct 2024 207th Steffan153 🇫🇮 843 119 294ms 1 Jul 2024 207th edsrzf 🇳🇿 843 119 9ms 13 Jan 2025 209th IanUtley 843 122 16ms 28 Jan 2024 210th jared-hughes 842 123 17ms 8 Sep 2022 210th quimey 842 123 15ms 4 Jul 2023 210th htareque 842 123 11ms 17 Oct 2023 213th GrayJoKing 🇦🇺 842 152 1,417ms 24 Jul 2025 214th pardouin 🇫🇷 842 160 2,702ms 14 Nov 2024 215th emplv 🇱🇻 842 217 301ms 19 Feb 2022 216th Lydxn 🇨🇦 841 31 4ms 28 Jul 2023 216th GrayJoKing 🇦🇺 841 31 4ms 3 Aug 2023 218th clockworknazo 841 84 22ms 13 Oct 2022 218th ovs-code 🇩🇪 841 84 20ms 7 Feb 2023 218th Steffan153 🇫🇮 841 84 19ms 7 Feb 2023 218th GrayJoKing 🇦🇺 841 84 20ms 12 Feb 2023 218th xsot 🇸🇬 841 84 18ms 6 Apr 2024 218th edsrzf 🇳🇿 841 84 19ms 9 Nov 2025 224th JayXon 🇺🇸 841 87 145ms 17 Aug 2024 225th Steffan153 🇫🇮 841 98 434ms 21 Jan 2024 226th namelessiw 841 163 436ms 1 Aug 2025 227th m-tkach 🇺🇦 841 188 32ms 9 Feb 2026 228th nwellnhof 🇩🇪 840 57 1,182ms 15 Feb 2022 229th nwellnhof 🇩🇪 840 167 450ms 16 Feb 2022 229th MostParsingVex 840 167 62ms 3 Jan 2025 231st edsrzf 🇳🇿 839 123 6ms 11 Aug 2025 232nd JayXon 🇺🇸 839 140 2ms 21 Feb 2022 233rd bitsandbeyond 🇳🇱 838 69 386ms 9 Oct 2025 234th xsot 🇸🇬 838 75 2ms 23 Feb 2026 235th CLOStrophobic 🇮🇹 838 158 153ms 26 May 2025 236th edsrzf 🇳🇿 838 223 240ms 10 Jun 2025 237th JayXon 🇺🇸 837 161 467ms 14 Jul 2023 238th btjones0 836 124 16ms 25 Feb 2022 238th SirBogman 🇺🇸 836 124 16ms 7 May 2022 238th commandz0 🇺🇸 836 124 17ms 23 Mar 2025 First Prev 161–240 of 1,190 Next Last