Head-to-Head Comparison · Alternative to Knack · 🗄️ databases
Knack vs REI3
A sober business-app builder with forms, reports, roles, workflows, and no per-user meter. Here is how REI3 ($0/mo open source) stacks up against Knack ($59/mo) across cost, hosting, data privacy, and real-world trade-offs.
Knack vs REI3 Specification Matrix
facts verified 2026-08-10
| Dimension | Knack (Paid) | REI3 (Replacement) |
|---|---|---|
| Monthly Price | $59 / mo | $0 / mo |
| 1-Year Cost (1 seat) | $708 / yr | $0 / yr (Save $708) |
| 1-Year Cost (5 seats) | $3,540 / yr | $0 / yr (Save $3,540) |
| 1-Year Cost (10 seats) | $7,080 / yr | $0 / yr (Save $7,080) |
| Source & License | Proprietary SaaS | open source MIT |
| Where It Runs | Vendor Cloud | Self-host (your server) |
| Platforms | Web / Cloud | desktopmobilewebself-hostedone-click install |
| GitHub Stars | — | ★ 571 (active aug 2026) |
Deep Dive: Switching from Knack to REI3
Trade-offs, installation & data architecture
What you trade away
Its utilitarian self-hosted business interfaces are less polished for branded external portals and nontechnical customer access than Knack.
How to deploy REI3
Native Linux/Windows server package or Docker Compose, connected to PostgreSQL
What it takes to run
You must provision PostgreSQL and configure a server/reverse proxy; it is not a managed one-click workspace
Where your data lives
Human-readable application records and configuration live in a PostgreSQL database controlled by the operator
Why fork REI3 instead of vibe-coding a Knack clone?
The core loop is buildable, but a dependable replacement becomes a real weekend or multi-day project. For Knack, build a small hosted database app with pages, forms, and role-based views. The hard boundary is managed hosting, schema builder, permissions, integrations, and support, plus data model flexibility, collaboration, and integrations.
Knack vs REI3 FAQ
Is REI3 a good free alternative to Knack?+
Yes. REI3 is a verified open-source (MIT) replacement for Knack. A sober business-app builder with forms, reports, roles, workflows, and no per-user meter.
What is the catch when switching from Knack to REI3?+
Its utilitarian self-hosted business interfaces are less polished for branded external portals and nontechnical customer access than Knack.
How much do you save switching from Knack to REI3?+
Knack costs $59/mo ($708/yr) per seat, whereas REI3 is $0/mo. Switching saves $708/yr for a solo user, $3,540/yr for a 5-person team, and $7,080/yr for a 10-person team.
How do I install or self-host REI3 instead of Knack?+
Install: Native Linux/Windows server package or Docker Compose, connected to PostgreSQL. Setup: You must provision PostgreSQL and configure a server/reverse proxy; it is not a managed one-click workspace
