Runway is, deservedly, the most-praised AI video tool of the last two years. Their model series, their professional editor, their ecosystem — none of it is fluff. ZSky AI is a newer, free, unlimited alternative.

This post is mostly about pricing, because that's where the comparison gets interesting. The quality conversation matters too and I'll get to it. But for daily-generation use cases, the cost math is brutal in one direction.

The Snapshot

ZSky AI Runway

Cost (free tier) Free, unlimited Limited credits, then paywall

Cost (entry paid) $19/mo $15/mo (Standard)

Cost (heavy use) $79/mo (Max plan) $35–$95/mo + per-credit overages

Credit system None on free Yes (credits per generation)

Editor Basic Professional NLE

Model lineup Curated Multiple (Gen-3 Alpha, etc.)

Image-to-video Yes Yes

Text-to-video Yes Yes

Green-screen / rotoscope Limited Yes (industry-grade)

Where Runway Wins (Be Honest)

Runway is genuinely excellent at a lot of things.…