When comparing Submit JSON and Headlessforms, the biggest differences are pricing model, submission limits, and overall product focus.
Headlessforms has a free plan and paid tiers starting at $4.50/month with per-form submission limits. Submit JSON's closest paid tier starts at $15/month with 10,000 submissions, and scales to 50,000 submissions at $49/month.
Headlessforms can be a fit if you need per-form submission scaling plus hosted form-builder capabilities.
If you want an API-first backend that gives you full control over UX and works cleanly with modern JavaScript stacks, Submit JSON is usually the stronger fit.
Pricing and limits verified from public pricing/docs pages in April 2026; competitor plans may change over time.
Google Sheets integration