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?
Jacobi Symbol 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 561st bizy-coder 503 151 503ms 27 Nov 2025 562nd rak1507 🇬🇧 503 161 17ms 8 Feb 2023 562nd StefanHabel 🇨🇦 503 161 17ms 26 Mar 2023 564th Shanethegamer 🇺🇸 502 349 68ms 20 May 2022 565th CLOStrophobic 🇮🇹 500 162 18ms 23 Jan 2025 565th andrewjc2000 500 162 17ms 18 Aug 2025 567th varhammer 500 288 6ms 13 Dec 2023 568th Shanethegamer 🇺🇸 495 133 3ms 12 May 2022 568th MeWhenI 🇻🇦 495 133 5ms 16 Apr 2023 570th HumanoidCPU 494 238 2,738ms 26 Oct 2024 571st RYNO8 491 165 18ms 16 Aug 2022 571st inverseLorentz 🇦🇺 491 165 11ms 24 Mar 2024 571st edsrzf 🇳🇿 491 165 10ms 17 days ago 574th BREMAUCY 🇫🇷 488 166 17ms 30 May 2023 575th janbehrens 🇩🇪 487 130 10ms 3 Jul 2023 576th Shanethegamer 🇺🇸 487 216 2ms 20 May 2022 577th MeWhenI 🇻🇦 486 227 64ms 6 Nov 2023 578th RDShah 485 167 12ms 22 May 2022 579th jared-hughes 482 108 35ms 26 Dec 2023 580th aksyristos 482 168 18ms 25 Jan 2023 581st jtaxen 479 169 18ms 1 Apr 2024 581st Andrey2001 479 169 16ms 17 Dec 2025 583rd MeWhenI 🇻🇦 478 148 156ms 25 Oct 2024 584th MeWhenI 🇻🇦 478 265 15ms 26 Aug 2023 585th commandz0 🇺🇸 477 159 467ms 1 Sep 2025 585th TheZwierzLF 🇵🇱 477 159 538ms 23 Nov 2025 587th IISResetMe 476 159 316ms 3 Jan 2026 588th Alex-x90 🇺🇸 476 170 18ms 15 Dec 2023 588th TheZwierzLF 🇵🇱 476 170 17ms 22 May 2025 590th stefangimmillaro 473 110 35ms 12 May 2025 591st SniperSmiley 🇺🇸 471 172 18ms 29 Jun 2022 591st adoxography 471 172 17ms 8 Aug 2022 593rd MeWhenI 🇻🇦 471 301 1,454ms 25 May 2022 594th neihousaigaai 468 173 10ms 17 May 2022 595th acollett89 468 177 12ms 4 Aug 2025 596th dokutan 466 168 562ms 7 Apr 2024 597th KatieLG 🇬🇧 465 112 36ms 2 Oct 2025 598th Bonjour27891 🇻🇳 465 174 17ms 5 Jul 2022 599th croc54 463 175 18ms 8 Jan 2025 600th emgordon154 462 220 4ms 3 Jan 2025 601st MichalMarsalek 🇨🇿 460 176 10ms 20 May 2022 602nd GolfingSuccess 🇬🇷 458 241 71ms 19 Sep 2023 603rd fgrosshans 🇫🇷 457 177 11ms 3 Nov 2022 604th Natanaelel 🇸🇪 456 114 36ms 17 Jul 2023 605th MaxElf999 455 178 17ms 27 Sep 2022 605th za3k 455 178 11ms 14 Dec 2022 607th MeWhenI 🇻🇦 455 253 623ms 11 May 2022 608th BambooleanLogic 🇸🇪 453 183 12ms 15 Nov 2022 609th MeWhenI 🇻🇦 451 567 15ms 15 Nov 2023 610th Andrey2001 449 169 485ms 28 Jan 2026 611th JOrE20 448 391 27ms 30 Jan 2026 612th Eilonlif 🇮🇱 447 181 11ms 15 Feb 2024 612th Aquateraneal 🇺🇸 447 181 12ms 16 days ago 614th mbittner20 445 182 11ms 27 May 2023 614th rollershutter 445 182 11ms 4 Jul 2024 616th frankgraziano 443 143 12ms 7 Mar 2025 617th tomh1012 442 183 17ms 24 Feb 2026 618th sleepyStick 440 184 17ms 15 Jul 2022 619th jerrandolph 439 269 330ms 1 Oct 2025 620th SirFireball3521 438 185 19ms 6 Mar 2023 620th CutSandstone 438 185 17ms 4 Jul 2024 622nd nullie 435 186 18ms 8 Jun 2022 623rd scpchicken 🇵🇼 433 187 17ms 4 Feb 2023 624th martinnorling 🇸🇪 431 188 17ms 10 May 2022 624th bac0id 431 188 17ms 5 Jul 2024 626th 0dyse 430 250 2ms 12 May 2025 627th AstroOrbis 428 189 17ms 12 Jul 2025 628th roguh 🇬🇹 428 246 2ms 18 Oct 2024 629th Lv0Sys 🇵🇱 427 122 35ms 7 Dec 2025 630th hiichbindermax 426 190 18ms 8 Feb 2023 631st MeWhenI 🇻🇦 425 207 17ms 1 Oct 2022 632nd aksyristos 425 291 2,869ms 12 Mar 2023 633rd jhpaques 🇫🇷 424 191 17ms 26 Jul 2022 633rd hellwue 424 191 19ms 8 Feb 2023 635th madeforlosers 422 192 18ms 13 Nov 2025 636th 0dyse 422 293 74ms 12 May 2025 637th msbranicky 420 193 17ms 10 Aug 2023 638th pschmid0 🇺🇸 420 225 5ms 29 Sep 2022 639th JRaspass 🇬🇧 419 157 4ms 8 May 2022 640th Pena86 415 195 18ms 14 Sep 2022 First Prev 561–640 of 728 Next Last