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?
Kaprekar Numbers 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 719th Shanethegamer 🇺🇸 197 445 85ms 1 Nov 2024 719th dokutan 197 445 92ms 1 Nov 2024 719th MeWhenI 🇻🇦 197 445 90ms 2 Nov 2024 719th CaedenHarper 🇨🇦 197 445 95ms 16 Aug 2025 719th KatieLG-Transpiler 🇬🇧 197 445 85ms 9 Jan 2026 726th QeepQeep 196 2,960 2ms 10 Nov 2024 726th Short-C0de 🇺🇸 196 2,960 2ms 14 Nov 2024 728th brimstonetrader 194 353 778ms 5 Nov 2024 729th KatieLG 🇬🇧 194 630 6ms 21 Feb 2026 730th CLOStrophobic 🇮🇹 193 356 4,507ms 9 Feb 2025 731st HumanoidCPU 189 449 39ms 1 Nov 2024 731st dokutan 189 449 39ms 1 Nov 2024 731st KatieLG 🇬🇧 189 449 39ms 1 Nov 2024 731st Shanethegamer 🇺🇸 189 449 40ms 1 Nov 2024 731st MeWhenI 🇻🇦 189 449 41ms 2 Nov 2024 731st CaedenHarper 🇨🇦 189 449 42ms 16 Aug 2025 731st gigaprofisi 🇺🇸 189 449 41ms 5 Nov 2025 738th KatieLG 🇬🇧 188 1,387 5ms 1 Nov 2024 739th Shanethegamer 🇺🇸 187 444 65ms 22 Nov 2024 740th HumanoidCPU 186 446 68ms 27 Jan 2025 741st KatieLG 🇬🇧 186 447 68ms 1 Nov 2024 741st MeWhenI 🇻🇦 186 447 62ms 2 Nov 2024 741st CaedenHarper 🇨🇦 186 447 65ms 25 Jan 2025 741st KatieLG-Transpiler 🇬🇧 186 447 61ms 9 Jan 2026 745th HumanoidCPU 184 519 111ms 1 Nov 2024 745th Shanethegamer 🇺🇸 184 519 110ms 1 Nov 2024 745th KatieLG 🇬🇧 184 519 117ms 1 Nov 2024 745th dokutan 184 519 108ms 1 Nov 2024 745th MeWhenI 🇻🇦 184 519 112ms 2 Nov 2024 745th CaedenHarper 🇨🇦 184 519 107ms 25 Jan 2025 745th KatieLG-Transpiler 🇬🇧 184 519 118ms 9 Jan 2026 752nd HumanoidCPU 182 449 120ms 1 Nov 2024 752nd dokutan 182 449 117ms 1 Nov 2024 752nd KatieLG 🇬🇧 182 449 126ms 1 Nov 2024 752nd Shanethegamer 🇺🇸 182 449 116ms 1 Nov 2024 752nd MeWhenI 🇻🇦 182 449 125ms 2 Nov 2024 752nd CaedenHarper 🇨🇦 182 449 124ms 16 Aug 2025 758th HumanoidCPU 179 460 106ms 1 Nov 2024 758th dokutan 179 460 110ms 1 Nov 2024 758th MeWhenI 🇻🇦 179 460 109ms 2 Nov 2024 758th klixel 🇨🇦 179 460 118ms 15 Nov 2024 758th Shanethegamer 🇺🇸 179 460 112ms 20 Feb 2025 758th CaedenHarper 🇨🇦 179 460 115ms 16 Aug 2025 764th HumanoidCPU 176 515 3ms 1 Nov 2024 765th adamnielson42 🇺🇸 174 395 4,427ms 3 Dec 2024 766th dokutan 174 434 39ms 1 Nov 2024 767th JOrE20 174 436 41ms 2 Feb 2026 768th dokutan 174 475 60ms 1 Nov 2024 768th Shanethegamer 🇺🇸 174 475 55ms 1 Nov 2024 768th CaedenHarper 🇨🇦 174 475 49ms 23 Jan 2025 768th HumanoidCPU 174 475 58ms 28 Nov 2025 772nd Blendi-Goose 173 387 1ms 7 Oct 2025 773rd MeWhenI 🇻🇦 173 455 39ms 2 Nov 2024 774th HumanoidCPU 172 441 38ms 1 Nov 2024 774th KatieLG 🇬🇧 172 441 38ms 1 Nov 2024 774th Shanethegamer 🇺🇸 172 441 37ms 1 Nov 2024 774th MeWhenI 🇻🇦 172 441 39ms 2 Nov 2024 774th CaedenHarper 🇨🇦 172 441 38ms 25 Jan 2025 779th dokutan 170 392 117ms 29 Dec 2025 780th ocefra 170 393 93ms 25 Dec 2024 781st KatieLG-Transpiler 🇬🇧 170 445 38ms 9 Jan 2026 782nd dokutan 170 470 328ms 24 Sep 2025 782nd Jacob385 170 470 468ms 27 Oct 2025 782nd HumanoidCPU 170 470 522ms 8 Nov 2025 785th HumanoidCPU 167 455 2ms 1 Nov 2024 785th dokutan 167 455 2ms 1 Nov 2024 785th KatieLG 🇬🇧 167 455 2ms 1 Nov 2024 785th Shanethegamer 🇺🇸 167 455 2ms 1 Nov 2024 785th MeWhenI 🇻🇦 167 455 2ms 2 Nov 2024 785th CaedenHarper 🇨🇦 167 455 2ms 16 Aug 2025 791st Shanethegamer 🇺🇸 167 471 467ms 1 Nov 2024 792nd KatieLG 🇬🇧 167 472 42ms 1 Nov 2024 792nd MeWhenI 🇻🇦 167 472 494ms 2 Nov 2024 792nd CaedenHarper 🇨🇦 167 472 448ms 24 Jan 2025 795th KatieLG-Transpiler 🇬🇧 166 459 2ms 9 Jan 2026 796th HumanoidCPU 166 473 464ms 1 Nov 2024 797th HumanoidCPU 165 441 3ms 1 Nov 2024 797th dokutan 165 441 3ms 1 Nov 2024 797th KatieLG 🇬🇧 165 441 3ms 1 Nov 2024 797th Shanethegamer 🇺🇸 165 441 3ms 1 Nov 2024 First Prev 721–800 of 1,113 Next Last