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Calculate conveyor speed and length, content performance and solar savings with formulas, units and assumptions you can inspect.
- The full formula and variable definitions
- Units, conversions and worked examples
- Assumptions and practical limits
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- Live tools
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Live now — 7 calculators with open formulas
- Free tool
Belt Speed Calculator
v = (π × D × n) / 60
- Belt speed
- m/s
- Belt speed
- ft/min
- Belt speed
- ft/s
- Pulley speed
- rpm
No signup · formula shown
- Free tool
Pulley Speed Calculator
N₂ = N₁ × D₁ / D₂; v = π × D₁ × N₁ / 60
- Diameter ratio
- driven:driver
- Speed ratio
- driven:driver
- Driven pulley speed
- rpm
- Belt linear speed
- m/s
- Belt linear speed
- ft/min
No signup · formula shown
- Free tool
Belt Length Calculator
L = 2√(C² − Δ²) + π(D₁ + D₂)/2 + 2Δ asin(Δ/C); Δ = (D₁ − D₂)/2
- Geometric length
- mm
- Length incl. allowance
- mm
- Length incl. allowance
- m
- Length incl. allowance
- ft
No signup · formula shown
- Free tool
Conveyor Belt Roll Length Calculator
L = π × (D² − d²) / (4t); Layers = (D − d) / (2t)
- Estimated belt length
- mm
- Estimated belt length
- m
- Estimated belt length
- ft
- Approximate radial layers
- layers
No signup · formula shown
- Free tool
Solar Savings Calculator
Saving_y = Yield × (1 − d)^(y−1) × Tariff − Opex
- Year-1 operating saving
- USD
- First-year simple payback
- years
- Lifetime operating saving
- USD
- Lifetime net after cost
- USD
- Simple return after cost
- %
No signup · formula shown
- Free tool
SEO ROI Calculator
Visits = Volume × CTR; Conversions = Visits × CVR; Revenue = Conversions × Value
- Forecast organic visits
- visits/month
- Forecast conversions
- conversions/month
- Forecast attributed revenue
- USD/month
- Revenue-based return proxy
- %
- Break-even conversions
- conversions/month
No signup · formula shown
- Free tool
Content ROI Calculator
RPOV = Revenue / Sessions × 1000 = CVR × AOV × 1000
- Monthly attributed revenue
- USD
- Revenue per 1,000 sessions
- USD
- Revenue-based return proxy
- %
- Cost per acquisition
- USD
No signup · formula shown
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Every calculator shows its formula, its units and its assumptions. No account, no email wall, no result held back.
Belt Speed Calculator
Belt speed from pulley diameter and motor RPM
- In
- Effective diameter, shaft RPM, gear ratio, optional belt slip
- Out
- m/s · ft/min · ft/s
Pulley Speed Calculator
Driven-pulley RPM and belt linear speed from a two-pulley drive
- In
- Driver diameter, driver RPM, driven diameter
- Out
- Speed ratio · driven RPM · m/s · ft/min
Conveyor Belt Roll Length Calculator
Estimate how much belt remains wound on a cylindrical core
- In
- Roll diameter, core diameter, total belt thickness
- Out
- Estimated mm · m · ft · radial layers
Content ROI Calculator
Attributed revenue per 1,000 organic sessions
- In
- Organic sessions, conversion rate, value, content cost
- Out
- Revenue per 1,000 sessions · return proxy
SEO ROI Calculator
Forecast traffic, conversions and revenue from a keyword opportunity
- In
- Search volume, CTR, conversion rate, value, monthly cost
- Out
- Visits · conversions · revenue · return proxy
Solar Savings Calculator
Illustrative savings from your own annual kWh estimate
- In
- System cost, annual kWh, electricity value, degradation
- Out
- First-year payback estimate · net saving
Why Newlii
A useful result should be possible to check
- 01
Formula shown
Every calculator publishes the equation it uses and defines each input, so the result is reproducible.
- 02
Limits stated
Assumptions and boundary conditions sit beside the result instead of being hidden in fine print.
- 03
No access gate
The current tools require no account or email address, and their inputs stay in the browser.
- 04
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