Form.io
JSON-powered form and API platform for developers, with an open-source core.
About
Form.io is a developer-oriented form platform founded in 2015 in the United States. The pitch is that every form you build in the drag-and-drop builder is really a JSON schema, and every schema automatically gets a REST API for submissions, plus a PDF server, file storage, and workflow hooks. The core server repository on GitHub carries 2,323 stars and is under the OSL-3.0 license, while the client renderer is MIT; the commercial platform adds SSO, audit logs, multi-tenancy, and HIPAA-ready deployment options. Directory listings put paid plans from around $25 per month, with enterprise and self-hosted tiers priced higher. It is aimed at teams embedding complex forms into their own products rather than at casual survey makers.
What it can do
- Drag-and-drop builder emitting pure JSON schemas
- Auto-generated REST APIs for every form
- Conditional logic, validation, and multi-page wizards
- PDF generation, file uploads, and e-signatures
- SSO, audit logs, and HIPAA-ready enterprise tier
Setup
Self-host the open-source server with Docker, or sign up for the hosted platform and build in the drag-and-drop builder.
Prerequisites
Node.js and MongoDB for self-hosting; an account for the hosted platform.
Use cases
Works with
Trust score — 7/10
Scored 7/10 (verified tier, metrics-v1). Evidence: 2015 founding and pricing bands from independent software directories; 2,323 stars and OSL-3.0 license read from the GitHub API. Strengths: JSON-first architecture with auto-generated APIs is genuinely developer-friendly; open core plus serious enterprise controls. Docked for: (1) commercial pricing is opaque and clearly aimed upmarket; (2) smaller community and ecosystem than the big SaaS form builders; (3) self-hosting is real work. License: OSL-3.0 (server); MIT (client renderer).
★ 2,323 GitHub stars
How the trust score is built
Full methodology →- Adoption · stars/downloads, log-scaled vs peers
- 6.0/10
- Maintenance · recency, releases, issue load
- 8.0/10
- Openness · license + docs
- 8.0/10
- Manual review · sanity read + red-flag check
- 7.0/10
- · 2,323 GitHub stars on formio/formio; pushed 2026-10-14 (verified via GitHub API)
- · Founded 2015, United States; JSON-schema forms with auto-generated REST APIs
- · Enterprise tier adds SSO, audit logs, multi-tenancy, HIPAA-ready deployment
- · manual review: commercial pricing opaque and upmarket; self-hosting is real work
Sources
Every fact above was checked against these sources. Where a claim comes from the provider and couldn't be independently verified, the text says so.