Free tools · Calculators
Calculators
Deterministic calculators where the answer is a number: belt and pulley speed, installed and rolled belt length, solar payback, SEO forecasts and content ROI. Each one publishes the formula so you can check the result rather than trusting it.
- 7 assets
- updated 2025-08
Calculators
Everything in Calculators
Every card states what the asset delivers, what it costs and when it was last updated.
Belt Speed Calculator
Belt speed from drive-pulley diameter and motor RPM, with gearbox and optional belt-slip correction.
- No signup
- Formula shown
- updated 2026-09
Free
Pulley Speed Calculator
Driven-pulley RPM and belt linear speed from two pulley diameters and driver RPM.
- No signup
- Formula shown
- updated 2026-09
Free
Belt Length Calculator
Geometric belt length for a simple open two-pulley path.
- No signup
- Formula shown
- updated 2026-09
Free
Conveyor Belt Roll Length Calculator
Estimated belt inventory on a roll from outside diameter, core diameter and thickness.
- No signup
- Formula shown
- updated 2026-09
Free
Solar Savings Calculator
Illustrative solar operating savings and simple payback from your own annual kWh estimate.
- No signup
- Formula shown
- updated 2026-09
Free
SEO ROI Calculator
Forecast organic visits, conversions and attributed revenue from a keyword opportunity.
- No signup
- Formula shown
- updated 2026-09
Free
Content ROI Calculator
Attributed revenue per 1,000 organic sessions and a revenue-based content return proxy.
- No signup
- Formula shown
- updated 2026-09
Free
Questions
Common questions
- Why do these show the formula?
- Because a number you cannot check is not usable in engineering or finance work. If the formula is visible, you can see when the tool does not apply to your case — which matters more than the answer itself.
- Are the calculators really free?
- Yes, with no account and no email wall. They exist to demonstrate how Newlii builds things; the paid assets are datasets, templates and agent runs.
- Can I embed one on my own site?
- Not currently. Licensing and embed support are on the roadmap — tell us if you need it and it moves up.
Start with the task
Tell us what you need to get done.
Describe the calculation you need and find the closest free tool. Product requests also help decide what Newlii builds next.
Free calculators need no signup · Methods and limits are shown