“AI video generator” covers two genuinely different jobs. Runway generates and edits open-ended video clips from text, images, or existing footage — useful for creative and general-purpose video work. Synthesia takes a different approach entirely, turning scripts into presenter-style videos with AI avatars, aimed at training, sales, and marketing content rather than open creative generation. This guide covers both, since which one is relevant depends entirely on which job you’re trying to do.
Quick Comparison
| Tool | Primary Use | Starting Price | Best For |
|---|---|---|---|
| Runway | General-purpose AI video and image generation/editing | Free (Standard $12–15/mo) | Creative and general-purpose video generation, including via API |
| Synthesia | AI avatar presenter videos from scripts | Free (Starter $18–29/mo) | Training, sales, and marketing videos without cameras or actors |
Tools Covered
Runway
Runway, at runwayml.com, is a general-purpose AI video and image generation and editing platform with API access for developers who want to build it into their own products.
Main Features
- Text-to-video and image-to-video generation
- Video editing and effects tools
- API access for developers
- Credit-based usage shared across generation tools
Best Suited Use Cases
Creative professionals, marketers, and developers who need open-ended AI video generation — not tied to a script-to-presenter format — or who want to integrate video generation into their own applications via API.
Pricing
Free plan with 125 one-time credits. Standard is $15/month (or $12/month billed annually) for 625 credits/month. Pro is $35/month (or $28/month annually) for 2,250 credits/month. Max is $95/month (or $76/month annually) for 9,500 credits/month. A custom-priced Enterprise tier is also available.
Limitations
Credits are shared across all generation types, so heavy video use can consume a monthly allowance quickly. It has no presenter-avatar or script-to-video feature — that’s not what it’s built for.
Read the full Runway profile for verified pricing details, pros and cons, and alternatives.
Synthesia
Synthesia, at synthesia.io, turns written scripts into videos featuring AI avatars, aimed squarely at training, sales enablement, and marketing content — not general creative video generation.
Main Features
- 125+ to 240+ AI avatars depending on plan
- AI Dubbing and translation into 70+ (up to 140+ on Enterprise) languages
- Branded, on-brand video pages and API access on higher tiers
- Interactive videos and multiple avatars per scene on Creator and above
Best Suited Use Cases
Teams producing training material, internal communications, sales enablement, or marketing videos at scale without hiring presenters, camera crews, or studios.
Pricing
Basic (free) includes 1,200 credits/month, about 10 minutes of video. Starter is $29/month or $18/month billed yearly ($264/year), with 14,500 credits/year (about 120 minutes/year). Creator is $89/month or $64/month billed yearly ($804/year), with 44,000 credits/year (about 360 minutes/year). Enterprise is custom-priced with unlimited video minutes.
Limitations
It’s not a general video-generation tool — there’s no open-ended text-to-video for non-presenter content. Free and Starter plans cap total video minutes per month/year, which can matter for high-volume production.
Read the full Synthesia profile for verified pricing details, pros and cons, and alternatives.
How to Choose
Because these tools serve different jobs, the decision usually isn’t between them — it’s about identifying which job you have:
- Content type: open-ended creative or product video (Runway) versus presenter-led training/marketing video (Synthesia)
- Need for an on-screen presenter: Synthesia’s avatars replace filming a person; Runway has no equivalent feature
- Developer integration: Runway offers API access for building video generation into other products
- Multi-language output: Synthesia’s AI Dubbing supports up to 140+ languages on Enterprise, useful for global training content
- Budget structure: both use credit-based pricing, but the credits measure different things (generation compute versus video minutes)
FAQ
Are Runway and Synthesia direct competitors?
Not really. They both generate AI video, but for different purposes — Runway for open-ended creative/general video generation, Synthesia for presenter-style avatar videos from scripts. Most buyers choose based on the content type they need, not by comparing the two head-to-head.
Do either of these tools have a free plan?
Yes, both offer a free tier: Runway with 125 one-time credits, and Synthesia’s Basic plan with 1,200 credits/month.
Can Runway create presenter-style avatar videos?
No, Runway is built for open-ended video and image generation and editing, not script-to-avatar presenter videos.
Does Synthesia support multiple languages?
Yes, AI Dubbing supports 70+ languages on Starter and Creator plans, and 140+ languages on Enterprise.
Final Thoughts
Runway and Synthesia both fall under “AI video generator,” but they answer different needs — Runway for general creative and API-driven video generation, Synthesia for script-to-avatar presenter videos. Rather than comparing them as rivals, match the tool to the specific kind of video you need to produce.
Explore each tool in more depth: