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?
Rijndael S-box 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 641st robin-scragg 273 313 17ms 6 Jun 2025 642nd JOrE20 273 391 43ms 18 Feb 2026 643rd MeWhenI 🇻🇦 273 866 3ms 1 Sep 2023 644th Mabeloid 🇳🇴 272 232 1ms 15 Oct 2025 645th KatieLG 🇬🇧 272 867 3ms 2 Sep 2023 645th KatieLG-Transpiler 🇬🇧 272 867 3ms 2 Sep 2023 647th crizin 🇰🇷 269 534 434ms 15 Sep 2023 648th Yewzir 🇧🇪 269 593 1,880ms 14 Nov 2025 649th HumanoidCPU 268 311 401ms 12 Nov 2025 650th bac0id 267 236 2ms 8 Jan 2025 651st Jacob385 267 538 478ms 4 Aug 2024 652nd msbranicky 267 590 2,757ms 11 Jan 2025 653rd JOrE20 267 768 4ms 29 Jan 2026 654th InigoK 🇺🇸 267 883 3ms 6 Aug 2025 655th trinityy-7 266 237 1ms 10 Oct 2023 656th aksyristos 266 321 14ms 11 Sep 2023 657th KatieLG 🇬🇧 266 769 3ms 11 Aug 2024 657th Shanethegamer 🇺🇸 266 769 3ms 11 Aug 2024 657th HumanoidCPU 266 769 3ms 13 Aug 2024 657th KatieLG-Transpiler 🇬🇧 266 769 3ms 16 Aug 2024 657th Mabeloid 🇳🇴 266 769 4ms 21 Sep 2024 657th CaedenHarper 🇨🇦 266 769 3ms 22 Jan 2025 657th snoozingnewt 🇨🇦 266 769 3ms 28 Sep 2025 664th peachey2k2 262 240 2ms 22 Nov 2025 665th msbranicky 262 638 150ms 1 Sep 2023 666th c0d3-4-F00d 🇩🇪 261 241 2ms 4 Dec 2023 667th helbling 🇨🇭 260 242 1ms 25 Jul 2024 668th Shanethegamer 🇺🇸 260 781 22ms 1 Sep 2023 668th KatieLG 🇬🇧 260 781 23ms 2 Sep 2023 668th KatieLG-Transpiler 🇬🇧 260 781 22ms 2 Sep 2023 668th snoozingnewt 🇨🇦 260 781 22ms 5 Sep 2023 668th vgamula 🇺🇦 260 781 22ms 6 Sep 2023 668th HumanoidCPU 260 781 22ms 16 Apr 2024 668th Mabeloid 🇳🇴 260 781 22ms 21 Sep 2024 668th dokutan 260 781 22ms 18 Oct 2024 668th CaedenHarper 🇨🇦 260 781 23ms 22 Jan 2025 677th ndren 260 782 25ms 20 Jan 2025 677th Stockoh 🇫🇷 260 782 23ms 9 Jan 2026 679th Martymoose98 258 244 1ms 30 May 2025 679th prestosilver 🇺🇸 258 244 2ms 4 days ago 681st tomtheisen 🇺🇸 258 521 416ms 13 Feb 2025 682nd dokutan 257 652 115ms 29 Dec 2025 683rd JunkIce 253 338 10ms 13 Feb 2025 684th Shanethegamer 🇺🇸 253 782 71ms 1 Sep 2023 684th HumanoidCPU 253 782 66ms 27 May 2024 684th dokutan 253 782 71ms 30 Jul 2024 684th Mabeloid 🇳🇴 253 782 69ms 21 Sep 2024 684th CaedenHarper 🇨🇦 253 782 65ms 22 Jan 2025 689th KatieLG 🇬🇧 251 712 3ms 22 Aug 2024 690th KatieLG 🇬🇧 250 792 69ms 2 Sep 2023 691st 1231234md5 🇨🇳 249 344 17ms 12 Dec 2023 692nd blaztoma 🇱🇹 249 540 418ms 6 Sep 2025 693rd gigaprofisi 🇺🇸 248 254 2ms 16 Jul 2025 694th JOrE20 248 327 27ms 21 Feb 2026 695th dokutan 247 305 35ms 13 Mar 2025 696th JunkIce 247 338 438ms 13 Feb 2025 697th rak1507 🇬🇧 246 347 49ms 1 Sep 2023 698th kallmi28 🇨🇿 244 258 2ms 8 Nov 2023 699th dokutan 244 588 361ms 24 Sep 2025 700th dokutan 244 791 122ms 18 Oct 2024 701st KatieLG-Transpiler 🇬🇧 244 809 648ms 2 Sep 2023 702nd MeWhenI 🇻🇦 243 779 8ms 1 Sep 2023 702nd Shanethegamer 🇺🇸 243 779 9ms 1 Sep 2023 702nd HumanoidCPU 243 779 9ms 16 Apr 2024 702nd Mabeloid 🇳🇴 243 779 9ms 21 Sep 2024 702nd dokutan 243 779 9ms 18 Oct 2024 702nd CaedenHarper 🇨🇦 243 779 10ms 22 Jan 2025 708th Shanethegamer 🇺🇸 243 795 109ms 1 Sep 2023 708th KatieLG 🇬🇧 243 795 114ms 2 Sep 2023 708th KatieLG-Transpiler 🇬🇧 243 795 109ms 2 Sep 2023 708th msbranicky 243 795 111ms 11 Sep 2023 708th HumanoidCPU 243 795 104ms 16 Apr 2024 708th Mabeloid 🇳🇴 243 795 123ms 21 Sep 2024 708th CaedenHarper 🇨🇦 243 795 109ms 21 Jan 2025 708th JOrE20 243 795 118ms 10 Feb 2026 716th yzhs 🇩🇪 242 260 1ms 24 Mar 2024 717th msbranicky 242 596 2ms 10 Oct 2023 718th msbranicky 242 637 6ms 1 Sep 2023 719th snoozingnewt 🇨🇦 242 798 105ms 4 Sep 2023 720th MeWhenI 🇻🇦 241 800 109ms 1 Sep 2023 First Prev 641–720 of 1,412 Next Last