When comparing these two products, the main differences that stand out are cost, plan limits, and overall design philosophy.
Getform's starter plan starts at $19/month with 1,000 total submissions and 5 total forms. Compare that to Submit JSON's $5/month plan that sports a submission limit of 2,500 and 10 form endpoints. Getform's plans cost 4x as much as Submit JSON, and they offer 2.5x less submissions on average.
Getform has been around for a bit longer than Submit JSON, so it has some mature features like SMTP email sending that we will be adding shortly.
Regardless, it's another Formspree clone. Getform's HTML-first approach is their greatest strength, and also their greatest weakness.
In comparison, Submit JSON's API-first approach is more secure, versitile, and aligned with modern web development best practices.
Which is the best form backend for you? We think the answer is obvious, but we'll let you decide.