Most 'free OG generators' are one-page designers: paste a URL, screenshot, done — still manual, one at a time. OpenGraphAPI is a free image API: put the URL in your CMS, newsletter or store and every page, issue and product gets its own OG image automatically. 300 images/day free, no credit card; a small watermark marks free renders.
| OpenGraphAPI | Free OG designers | |
|---|---|---|
| Type | Image API (not a designer) | Manual one-page designers |
| Free tier | 300 images/day, watermarked | Unlimited but manual |
| Formats | 1200×630 PNG (OG standard) | Screenshot quality varies |
| Templates | 30 social templates, 10 themes | A few |
Start free — 300 images/day Read the docs
OpenGraphAPI's free tier is 300 renders/day without a card; paid plans remove the watermark and raise limits.