Synonyms for Unforced (same or very similar meaning)
WordNet sense 1 (not brought about by coercion or force):
willing, uncoerced
WordNet sense 2 (of your own free will or design; not forced or compelled):
voluntary
WordNet sense 3 (not resulting from undue effort; not forced):
unstrained
WordNet sense 4 (requiring or apparently requiring no effort):
effortless
From the ODE community, based on WordNet
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