The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 6 days. 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 881st LeeCamp 518 145 16ms 14 Feb 2022 881st hellwue 518 145 11ms 7 Feb 2023 881st adamnielson42 🇺🇸 518 145 23ms 8 Oct 2024 881st Mabeloid 🇳🇴 518 145 26ms 4 May 2025 881st te-chnical 518 145 16ms 9 Jul 2025 886th retrohun 515 122 2ms 23 days ago 887th karhuthebear 515 146 17ms 6 May 2022 887th Bonjour27891 🇻🇳 515 146 10ms 17 Jul 2022 887th Player01osu 515 146 10ms 28 Oct 2023 890th nephila-nacrea 🇬🇧 514 79 6ms 20 Feb 2022 891st Sciman101 512 192 2ms 27 Mar 2025 892nd Bodo171 511 147 19ms 7 Dec 2022 892nd vgamula 🇺🇦 511 147 18ms 6 Nov 2023 892nd croc54 511 147 17ms 27 Jan 2025 895th MeWhenI 🇻🇦 510 370 26ms 14 Feb 2022 896th dokutan 509 193 2ms 13 Jan 2025 897th MeWhenI 🇻🇦 509 367 221ms 15 Feb 2022 898th davecame 508 148 29ms 18 Sep 2023 899th rucin93 🇵🇱 506 79 36ms 31 May 2025 900th Yewzir 🇧🇪 505 63 69ms 11 Mar 2024 901st namcartoon06 504 278 2,819ms 30 Jun 2023 902nd HumanoidCPU 503 132 480ms 29 Sep 2024 903rd adamnielson42 🇺🇸 503 146 11ms 2 Jun 2023 904th sleepyStick 501 150 16ms 15 Jul 2022 904th galloj 🇨🇿 501 150 16ms 9 Jan 2023 904th cingulataluke 501 150 11ms 27 Aug 2023 904th CutSandstone 501 150 18ms 8 Jul 2024 908th KatieLG 🇬🇧 501 365 285ms 1 Oct 2022 909th msbranicky 499 267 2ms 12 Aug 2023 910th MeWhenI 🇻🇦 499 317 33ms 6 Jun 2023 911th jacklynnepenick 498 151 16ms 15 Feb 2022 911th ssbhatt4321 498 151 19ms 11 Jun 2023 911th thienudomsrirungruang 498 151 17ms 16 Apr 2024 911th mishak-sys 498 151 25ms 24 Feb 2025 915th nyoshe 498 234 2ms 4 Jul 2023 916th MeWhenI 🇻🇦 497 117 164ms 3 Aug 2024 917th MeWhenI 🇻🇦 497 168 5ms 28 May 2023 918th MaxElf999 497 321 427ms 20 Aug 2024 919th edsrzf 🇳🇿 495 160 105ms 10 Nov 2025 920th MeWhenI 🇻🇦 495 303 38ms 6 Sep 2022 921st bstrat 494 70 3ms 29 May 2024 922nd TheBlupper 494 152 15ms 8 Nov 2022 922nd yokasuretsu 494 152 15ms 14 Jan 2025 922nd islptng 494 152 16ms 14 Oct 2025 925th MeWhenI 🇻🇦 494 236 2ms 25 Aug 2023 925th keelimeguy 🇺🇸 494 236 2ms 5 Nov 2023 927th hjcafaroUC 491 153 14ms 20 Aug 2022 927th LogicalJoe 491 153 10ms 29 Nov 2022 929th emplv 🇱🇻 491 170 5ms 30 Apr 2024 930th Schmitt-Very-Cool 491 325 495ms 3 Oct 2025 931st adamnielson42 🇺🇸 490 58 4ms 10 Jan 2024 932nd dokutan 490 232 39ms 26 Aug 2024 933rd AutumnWind75 490 286 445ms 10 Dec 2025 934th KatieLG-Transpiler 🇬🇧 488 154 91ms 4 Nov 2022 934th stertooy 🇧🇪 488 154 16ms 14 Jun 2024 936th CaedenHarper 🇨🇦 487 82 40ms 13 Sep 2025 937th DialFrost 🇸🇬 487 129 2ms 31 May 2025 938th MeWhenI 🇻🇦 486 168 8ms 19 Apr 2024 939th MeWhenI 🇻🇦 486 608 47ms 15 Nov 2023 940th AbhilashaTandon 485 155 15ms 21 Nov 2022 940th aksyristos 485 155 10ms 29 Nov 2022 940th b10011 🇫🇮 485 155 16ms 21 Jan 2023 940th Stockoh 🇫🇷 485 155 15ms 17 Oct 2024 944th luuumine 🇫🇷 485 240 2ms 26 Nov 2025 945th yoshykai 485 329 441ms 8 Apr 2025 946th AstroOrbis 483 168 9ms 24 days ago 947th bac0id 483 330 399ms 27 Jun 2024 948th lionbryce 482 204 1ms 7 Aug 2024 949th Frowny 480 72 3ms 14 Feb 2022 950th genmeblog 480 169 8ms 11 Dec 2023 951st trist224 🇫🇷 479 157 10ms 29 Nov 2022 951st TaserTheFox 🇺🇸 479 157 16ms 20 Jan 2023 953rd pandapawskat 479 243 2ms 9 Dec 2022 954th dokutan 474 281 2ms 5 Aug 2024 955th HumanoidCPU 473 155 10ms 8 Oct 2024 956th neihousaigaai 473 159 20ms 20 Feb 2022 956th brimstonetrader 473 159 17ms 8 Jan 2024 956th qpwoeirut 473 159 10ms 19 Nov 2025 956th Emutis 🇱🇹 473 159 16ms 24 days ago 960th janbehrens 🇩🇪 472 177 4ms 6 Jul 2023 First Prev 881–960 of 1,185 Next Last