• Placid.app – commercial
• BannerBear – commercial
• ogimpact.sh – commercial
  • their template editor
  • their open source library
• Motif by imgix – auto-generates the card based on your page contents.
• og-image – open source, ready to be deployed on zeit. just one template, you need to edit the code to change it.

Do it yourself. All of these tools uses Chrome Headless, so you can just use:

• puppeteer installed locally.
• Browserless.io – you don’t have to install Chrome Headless yourself.
• puppeteer-serverless – render on your own AWS Lambda.

Related tools:

• CardPreview Tool – by placid.app

A note on speed: Generating images via Chrome Headless can take some seconds. Unless you are pre-generating them, the delay in making them can cause them not be be shown. Seems the behavior depends on the app. Telegram and WhatsApp start loading them when the link is pasted, even if the message is not submitted. If you submit the link before the image is ready, Telegram seems, usually, to attach the social card later once it is ready. WhatsApp Web however will not – if the link is sent early, there will be no social image.