The letters in FEASIBLE make 153 words of two letters or more. The longest is FEASIBLE at 8 letters, and the highest-scoring is FEASIBLE at 13 points.
No other single word uses all 8 letters of FEASIBLE. FEASIBLE has 8 letters: 4 vowels and 4 consonants, worth 13 points before any board bonuses.
8-letter words 1
7-letter words 3
bailees9befleas12beliefs12
6-letter words 9
abeles8abseil8bailee8beflea11belief11belies8fables11falsie9selfie9
5-letter words 28
abele7abies7ables7aisle5alefs8alifs8baels7bails7bales7basil7beefs10belie7biles7blase7easel5fable10fails8false8fease8feels8files8flabs10fleas8flees8flies8leafs8lease5sable7
4-letter words 56
able6ails4albs6alee4alef7ales4alif7bael6bail6bale6bals6base6beef9bees6bels6bias6bile6bise6blae6ease4eels4else4fail7feal7feel7fees7fibs9fila7file7fils7flab9flea7flee7ilea4isba6isle4labs6lase4leaf7leas4lees4leis4libs6lief7lies4life7sabe6safe7sail4sale4seal4seel4seif7self7sial4slab6
3-letter words 38
abs5ail3ais3alb5ale3als3bal5bas5bee5bel5bis5eel3efs6elf6els3fab8fas6fee6fib8fie6fil6ifs6lab5las3lea3lee3lei3lib5lie3lis3sab5sae3sal3sea3see3sei3sel3sib5
2-letter words 18
ab4ae2ai2al2as2ba4be4bi4ef5el2es2fa5if5is2la2li2ls2si2
Words are from our open word list and include some game-only words. Rude words are left out of this page; the unscrambler shows every valid word, lets you add blank tiles and filter by length.