The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 4 days. Why not try and solve them ahead of time?
ASCII Table 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 800th frnco 654 94 36ms 2 Jun 2022 800th stefangimmillaro 654 94 33ms 1 Aug 2022 803rd snoozingnewt 🇨🇦 654 170 1ms 2 Nov 2025 804th Betuaredead 654 181 62ms 8 Jan 2023 804th oceko 654 181 431ms 24 Mar 2023 806th Yewzir 🇧🇪 654 203 127ms 30 Apr 2023 806th arctouch-cristiannevianna 654 203 107ms 30 Nov 2023 808th SteveHales 653 124 80ms 15 Oct 2025 809th NewDefectus 🇮🇱 653 184 360ms 2 May 2022 810th toschug 652 135 4ms 4 Jan 2023 811th jared-hughes 652 150 10ms 27 Mar 2022 811th lifthrasiir 🇰🇷 652 150 11ms 23 Nov 2024 813th cingulataluke 651 104 10ms 26 Aug 2023 813th davecame 651 104 10ms 11 Oct 2023 813th RaBa21 🇭🇺 651 104 15ms 17 Jul 2025 816th krcs 🇵🇱 651 105 250ms 7 May 2022 817th Mabeloid 🇳🇴 650 150 2ms 25 Sep 2024 818th astdefu 650 182 64ms 8 Dec 2022 819th squid233 650 196 462ms 7 Nov 2025 820th duckyluuk 🇳🇱 650 265 1ms 29 Jan 2026 821st arcpolaris 649 185 396ms 9 Dec 2024 822nd snoozingnewt 🇨🇦 649 189 28ms 2 Nov 2025 823rd stefangimmillaro 647 136 5ms 2 Jul 2023 824th biocommando 🇫🇮 647 151 10ms 21 Aug 2023 824th Elkfoot2 647 151 13ms 10 Jan 2026 826th AlephSquirrel 647 155 3ms 29 Jul 2023 827th xbxbxb007 647 219 275ms 10 Jan 2024 828th rifatx 646 151 1ms 24 Jul 2024 829th Xwilarg 🇫🇷 646 186 389ms 5 Nov 2022 830th dokutan 646 200 91ms 21 Sep 2024 831st rollershutter 645 105 10ms 14 Oct 2024 831st solisolu 645 105 9ms 17 Oct 2025 833rd madeforlosers 645 169 39ms 25 Oct 2023 834th MikeColes 644 220 291ms 10 Aug 2022 835th GrayJoKing 🇦🇺 643 128 76ms 2 Jun 2022 836th DialFrost 🇸🇬 643 130 14ms 3 Mar 2025 837th uttumuttu 🇫🇮 643 152 11ms 8 Apr 2022 837th olleicua 🇺🇸 643 152 12ms 6 Feb 2024 839th vroup 🇩🇰 643 187 401ms 1 Oct 2022 839th Maximizer02 643 187 389ms 12 Mar 2024 839th bac0id 643 187 403ms 5 Jul 2024 842nd papsonic 643 191 30ms 22 Jun 2023 842nd Tim-ats-d 643 191 30ms 22 Jun 2023 844th MCausc78 🇺🇦 643 234 55ms 13 Jan 2023 845th AlephSquirrel 642 101 485ms 21 Jan 2024 846th connorslade 642 207 168ms 15 May 2022 847th Frowny 640 82 34ms 28 Mar 2022 848th SirFireball3521 640 85 128ms 29 Jul 2023 849th emgordon154 640 139 6ms 13 Dec 2024 850th snoozingnewt 🇨🇦 640 167 9ms 1 Nov 2025 851st prplz 🇦🇺 639 106 10ms 28 Mar 2022 851st blaztoma 🇱🇹 639 106 10ms 5 Jan 2026 853rd CarraUjilen 639 107 251ms 1 Aug 2022 853rd Arnaud-beep 🇫🇷 639 107 247ms 4 Aug 2022 855th two-bad 🇬🇧 639 153 10ms 6 Feb 2024 855th smclaughlin-cf 639 153 11ms 18 Mar 2025 857th snoozingnewt 🇨🇦 638 152 2,584ms 2 Nov 2025 858th Macweese 638 153 2ms 10 Jan 2026 858th isaiah0311 🇺🇸 638 153 2ms 26 Jan 2026 860th MeWhenI 🇻🇦 636 102 470ms 7 Jul 2025 861st yamhab 🇨🇦 636 209 146ms 14 Sep 2023 862nd GeorgeStechman 🇬🇧 635 154 12ms 7 Jun 2022 862nd denis-jasselette 635 154 10ms 18 Oct 2025 864th shinh 634 97 35ms 28 Jun 2022 865th Schmitt-Very-Cool 634 201 511ms 26 Sep 2025 866th loganmacdougall 🇨🇦 633 154 2ms 1 Nov 2022 867th snoozingnewt 🇨🇦 633 168 11ms 30 Dec 2025 868th MeWhenI 🇻🇦 633 180 7ms 31 Jul 2025 869th WalrusesAreAwesome 632 190 404ms 10 Jan 2025 870th dylanarmstrong 631 155 14ms 24 Jan 2024 871st annaproxy 631 202 661ms 2 Jan 2023 872nd GolfingSuccess 🇬🇷 630 145 1ms 12 Nov 2025 873rd bizy-coder 629 103 470ms 15 Jan 2024 874th Andriamanitra 🇫🇮 628 98 40ms 24 Sep 2022 874th DialFrost 🇸🇬 628 98 40ms 14 Jun 2024 876th snoozingnewt 🇨🇦 628 140 5ms 2 Nov 2025 877th Yewzir 🇧🇪 628 203 80ms 5 days ago 878th sultan 627 109 259ms 24 May 2022 878th TaserTheFox 🇺🇸 627 109 238ms 6 Jun 2023 880th ArmaanAS 627 156 10ms 25 Dec 2022 First Prev 801–880 of 2,312 Next Last