Formula
The method should be visible rather than treated as a black box.
Calculate without hiding the model
Calculators
Calculations you can inspect, challenge, and reuse.
Every Nortune calculator states its formula, assumptions, limitations, and how to interpret the result.
Publishing standard
What belongs in calculators.
The directory stays useful by separating product types and refusing unclear listings.
Assumptions
Defaults and ranges must be easy to change and understand.
Interpretation
A result card explains what the number does and does not mean.
Before use
Every tool page answers the operational questions.
- What information does the tool receive?
- Does anything leave the browser?
- Which assumptions shape the result?
- What is the pricing model?
- Where are the limitations and support routes?