How to say "endlessly" in Japanese

• 延々えんえんCommon
  adverb (with と), taru-adjectiveDescribes something going on and on without a break — a speech, a queue, a road stretching into the distance. The nuance is length that drags on, often to the point of tedium.
  彼かれのスピーチは延々えんえんと続つづいた。↗

  His speech went on and on.
• とめどなくCommon
  adverbCovers 'endlessly' as 'ceaselessly, nonstop': something pouring forth or continuing without pause, like tears, rain, or talk that flows on and on. The image is of an unbroken stream.
  彼女かのじょの目めから涙なみだがとめどなく流ながれていた。↗

  An endless flow of tears fell from her eyes.
• いつまでもJLPT N3approx.Common
  adverbThis is really the 'forever' word: time stretching on without limit — 'for good,' 'eternally,' or 'as long as one likes.' Choose it when English 'endlessly' means lasting indefinitely, not unceasing activity.
  私はいつまでも彼かれの名なを覚おぼえている。↗

  I still bear his name in mind.

Use 延々 for something continuing on and on, 「とめどなく」 for an unceasing flow or stream of activity, and 「いつまでも」 when 'endlessly' really means 'forever' or 'as long as one likes'.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 延々えんえんendlessly
• とめどなくendlessly
• いつまでもforever
• 際限なくさいげんなくad infinitum
• 限りなくかぎりなくunlimitedly
• だらだらsluggishly
• ごてごて(complain) endlessly