Kling AI 4.0 adds 30-second clips, stereo audio and lip sync

Kling 4.0 supports clips up to 30 seconds, ten keyframe images as input, 8,000-token prompts, stereo audio and multilingual lip sync, plus a lighter Flash variant. Against Wan 3.0 and Seedance 2.5 it holds its own without pulling ahead.

Why it matters: Near parity among the top video generators suggests rapid gains are levelling off, so competition shifts to length, audio and cost. Longer clips with keyframe control make the tools more usable in production workflows.