Synonyms of exacting

1 Syllable
hard, harsh, tough, strict, stern, trying
2 Syllables
pressing, fussy, carking, strictest, captious, upstream, hard-won, dragger, tiring, choosy, picky, choicy, fussier, heaton, weighty, stringent, grievous, squeamish, heat-on, taxing, rigid, stricter, choosier
3 Syllables
demanding, rigorous, conscientious, careful, onerous, exigent, cavillous, backbreaker, austere, painstaking, difficult, precise, finicky, uncordial, nit-picking, fussbudget, unsparing, imperious, severe, assiduous, hard-and-fast, fastidious, nit-picky, hard-shelled, unfeeling, ruffianly, critical, finicking, requiring, hurry-up, hard-working
4 Syllables
burdensome, tiresome, overtaxing, exceptive, ironhearted, oppressive, difficile, particular, picky-picky, depressive, unamiable, boresome, persnickety, exorbitant, high-priority
5 Syllables
superincumbent, overcritical, hypercritical, overfastidious, enervative, extortionate