Enter your operating targets
Add expected concurrent users, max response time, uptime target, and whether sensitive data is involved.
NFR SPEC CHECK
Non-Functional Requirements Builder
Turn expected load, latency, uptime, and data sensitivity into a structured non-functional requirements summary with throughput, latency, availability, and security tiers.
- Uses your inputs in a transparent calculation
- Instant result with practical next steps
- No signup required
Planning guidance only. Validate important decisions with customer evidence and your delivery team.
YOUR INPUTS
Build your result
Complete every field. The result updates only when you choose Calculate.
How it works
Get four NFR tiers
Each input maps to a throughput, latency, availability, or security tier describing what it implies architecturally.
See an overall rigor score
The four tiers combine into a 0-100 NFR rigor score so you know how demanding the system's non-functional needs really are.
Continue learning: Non-functional requirements for AI-assisted builds
Frequently asked questions
What are non-functional requirements?
Requirements about how a system performs rather than what it does — things like speed, scale, uptime, and security, as opposed to features.
Why does uptime target matter this early?
A 99.99% target implies multi-region redundancy and on-call processes; a 99% target does not. Deciding this early avoids re-architecting later.
How is the rigor score calculated?
Each of the four inputs maps to a tier with points based on how demanding it is (e.g. more concurrent users, lower latency, higher uptime, or sensitive data all raise the score), summed to 0-100.
Do I need to fill this in for every feature?
It's most useful at the system or major-feature level — small internal tools rarely need a full NFR pass, but anything user-facing at scale benefits from one.
What if I don't know my expected concurrent users yet?
Use a conservative estimate based on your current or projected user base; you can re-run this tool once real usage data comes in.
How We Compare
| Feature | MVPHub | Notion | Google Sheets |
|---|---|---|---|
| Structured 4-tier NFR breakdown | Included | Limited | Limited |
| Instant rigor scoring | Included | Not included | Not included |
| Architecture implications per tier | Included | Not included | Not included |
| No setup required | Included | Limited | Included |
Notion and Sheets can hold NFR values in a table, but neither derives tiers or an overall rigor score automatically.
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