Antonyms for careful

all:

careless.

cautious; painstaking:

incautious, heedless, loose, rash, careless, unwise, indiscreet, inconsiderate, idiotic, questionable, thoughtless, foolish, uncaring, inattentive, unscrupulous, inaccurate, inexact, uncareful, reckless, negligent, false, lax, unconcerned, irrational.

noun:

imprudent, indifferent, regardless, apathetic, injudicious, halfhearted, indiscreet, undemanding, unintentional, unplanned, venturesome, thoughtless, hurried, lackadaisical, inadvertent, asleep, dull, mindless, oblivious, impetuous, drowsy, inaccurate, unsafe, unguarded, undiscriminating, improvident, rash, inconsiderate, imprecise, inattentive.