Enter the tiles from your rack — use a blank for wildcard tiles — and the finder returns every word the official Scrabble dictionary allows, sorted by score. Filters for length, starting letter, and ending letter let you match the results to what the board will actually accept: hunting a seven-letter bingo is a different search than squeezing a word past a triple-word square.
For example, the rack A-E-I-N-R-S-T — famous among tournament players as one of the most productive racks in the game — produces bingos like RETINAS, RETAINS, NASTIER, and ANESTRI, each worth the 50-point bonus for using all seven tiles. The same search also lists every shorter option, because when the board is tight, the six-letter RETINA or the four-letter RAIN may be the only play that fits.
Three things, and it does them strictly: it finds every valid word your tiles allow (including the two-letter words that rescue dead turns), it validates each one against the official Scrabble word list so no play gets challenged off the board, and it ranks results by point value so the scoring comparison is done before you look. Blank tiles are fully supported — the engine tries all 26 letters in each blank's place and folds the results into one list.
While it's built around official Scrabble rules, the same engine drives tools for other games: Words With Friends uses a different dictionary and different tile values (a word that's a star play in one game can be invalid or mediocre in the other), Scrabble GO has its own modern word list, and the general anagram solver covers everything else.
Scrabble runs on two official word lists, and knowing which one your game uses matters more than most casual players realize. North American play uses the NASPA Word List; international and UK play uses Collins, which is substantially larger and admits thousands of words the American list rejects. A word finder that ignores this distinction hands you challengeable plays. Check which list your table or app enforces, set the finder to match, and see the Scrabble dictionary for how the lists differ and where to verify individual words.
The finder wins you the current turn; studying short lists wins you the next hundred games. The highest-return study material, in rough order:
Worth answering straight: in rated club or tournament play, yes — outside assistance is against the rules, and this tool is for between games, not during them. In casual play, it's a table rule; agree before you start. Where it's unambiguously fair game: post-game analysis (running your racks afterward to see what you missed is the fastest vocabulary builder in the game), solo practice, puzzle solving, and settling dictionary arguments after the tiles are back in the bag. Most players who improve quickly use it exactly this way — as a coach, not a ghostwriter.