The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 3 days. Why not try and solve them ahead of time?
CSS Colors 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 481st ovs-code 🇩🇪 410 753 2,795ms 3 Jun 2024 482nd alemelis 407 556 375ms 19 Jul 2024 483rd ovs-code 🇩🇪 407 718 2ms 13 Feb 2024 484th martinnorling 🇸🇪 406 612 10ms 18 Feb 2022 485th 5cw 🇺🇸 403 616 17ms 23 May 2025 486th rucin93 🇵🇱 402 580 181ms 31 Oct 2024 487th MathisBullinger 401 665 25ms 15 Nov 2021 488th AlephSquirrel 401 686 399ms 30 May 2023 489th lynn 401 728 2ms 22 Dec 2021 490th nickspoons 🇳🇿 400 499 32ms 15 Apr 2023 491st KasperKivimaeki 🇫🇮 400 773 2,926ms 19 Nov 2025 492nd andersk 🇺🇸 399 623 192ms 6 Oct 2020 493rd lynn 399 775 60ms 12 Jan 2022 494th GrayJoKing 🇦🇺 398 741 15ms 19 Jan 2023 495th UnderKoen 🇳🇱 398 917 4ms 20 Sep 2023 496th Seek64 🇩🇪 396 627 12ms 8 Oct 2024 497th hyvyys 395 675 12ms 18 Sep 2020 498th Bulmenisaurus 394 631 17ms 29 Jan 2025 498th aksyristos 394 631 12ms 32 mins ago 500th jared-hughes 394 695 2ms 12 Apr 2022 501st CaedenHarper 🇨🇦 393 856 6ms 4 Jan 2026 502nd sisyphus-ppcg 🇦🇺 392 634 17ms 11 Mar 2022 503rd lynn 392 783 449ms 23 Sep 2021 504th emplv 🇱🇻 391 860 7ms 2 Jul 2023 505th sean-niemann 🇺🇸 390 805 187ms 18 Nov 2023 506th lynn 389 638 17ms 27 Jul 2021 507th edsrzf 🇳🇿 389 642 6ms 7 Nov 2025 508th jared-hughes 389 685 11ms 3 Aug 2022 509th stefangimmillaro 389 795 790ms 16 Sep 2023 510th MattShaile 387 688 10ms 9 Apr 2022 511th edsrzf 🇳🇿 387 728 25ms 23 Jun 2025 512th saito-ta 🇯🇵 385 650 27ms 3 Oct 2024 513th AlephSquirrel 384 647 94ms 21 Jan 2024 514th stefangimmillaro 384 818 295ms 11 Nov 2023 515th stefangimmillaro 384 877 5ms 15 May 2022 516th stefangimmillaro 383 648 21ms 29 Dec 2022 516th blaztoma 🇱🇹 383 648 11ms 9 Sep 2025 518th janbehrens 🇩🇪 383 880 6ms 2 Jul 2023 519th olivermrose 🇺🇸 382 562 46ms 22 Sep 2021 520th CatsAreFluffy 382 697 17ms 1 Dec 2022 521st MeWhenI 🇻🇦 382 817 301ms 9 Feb 2023 522nd stefangimmillaro 380 806 563ms 6 Oct 2025 523rd CaedenHarper 🇨🇦 379 722 50ms 10 days ago 524th edsrzf 🇳🇿 379 809 477ms 24 Sep 2025 525th KatieLG 🇬🇧 379 962 5ms 8 Jan 2023 526th ovs-code 🇩🇪 378 661 14ms 25 Sep 2022 527th MeWhenI 🇻🇦 377 673 148ms 33 hours ago 528th tomh1012 377 892 5ms 5 Feb 2026 529th emgordon154 376 619 142ms 6 Sep 2024 530th snoozingnewt 🇨🇦 376 716 110ms 20 Feb 2026 531st edsrzf 🇳🇿 374 737 24ms 28 May 2025 532nd mathisfun271 373 665 11ms 5 Feb 2024 533rd BBoehm 🇩🇪 373 715 17ms 25 Dec 2020 534th jared-hughes 372 668 12ms 7 Jan 2023 535th radarek 🇵🇱 371 580 329ms 2 Jul 2025 536th m-tkach 🇺🇦 370 600 1,333ms 3 Jan 2024 537th jared-hughes 369 677 202ms 17 Jul 2022 538th lynn 369 741 4ms 7 Jan 2022 539th MeWhenI 🇻🇦 367 729 514ms 5 Mar 2022 540th MeWhenI 🇻🇦 367 808 8ms 12 Oct 2023 541st emgordon154 366 171 477ms 29 Apr 2025 542nd Natanaelel 🇸🇪 365 589 61ms 25 Feb 2026 543rd stefangimmillaro 365 856 287ms 16 Sep 2023 544th janbehrens 🇩🇪 364 443 368ms 21 Nov 2021 545th lynn 363 759 9ms 7 Jan 2022 546th jahakari 362 445 441ms 21 Nov 2021 547th ovs-code 🇩🇪 362 593 37ms 9 Jul 2024 548th Shanethegamer 🇺🇸 362 738 707ms 5 Mar 2022 549th Irratix 🇳🇱 360 597 38ms 5 Apr 2022 550th MeWhenI 🇻🇦 358 620 1,421ms 25 Mar 2024 551st dokutan 358 2,080 6ms 7 Sep 2023 552nd lynn 357 712 203ms 26 Aug 2021 553rd MeWhenI 🇻🇦 356 636 475ms 15 Feb 2023 554th kamenitxan 🇨🇿 354 187 245ms 8 Feb 2021 555th Bubbler-4 353 565 35ms 8 Dec 2021 556th SirBogman 🇺🇸 351 568 34ms 26 Aug 2022 557th Starwort 🇬🇧 351 708 12ms 26 Sep 2023 558th dokutan 351 8,623 3ms 8 Jun 2023 559th tetrogem 349 763 17ms 23 Aug 2025 560th edsrzf 🇳🇿 348 681 1,105ms 3 Sep 2025 First Prev 481–560 of 1,317 Next Last