spur-of-the-moment
adjective
• done without planning in advance; impulsive.
• "it was a spur-of-the-moment decision"
on the spur of the moment
• on impulse; without planning in advance.
• "I don't generally do things on the spur of the moment"
Similar:
impulsively,
on impulse,
impetuously,
without thinking,
without planning,
without premeditation,
unpremeditatedly,
impromptu,
spontaneously,
on the spot,
suddenly,
all of a sudden,
unexpectedly,
out of the blue,
