Solar Calculator: Estimate Solar Panel Cost & Savings Online

How Does Spectra Solar Calculator Work?

It works in 3 easy steps, no complicated formulas, no jargon:

Enter your monthly electricity bill – for example, ₹2,500.

Select your location – like Jaipur, Lucknow, or Pune.

See instant results – feasible plant size, cost and savings.

What is a Solar Calculator?

A solar calculator is like a planning head for your solar journey. Instead of calling multiple vendors and struggling with numbers, you just enter your details online on a solar panel calculator for home and get an instant idea.

For homeowners, it answers:

What will be the feasible plant size for me?
How much roof area do I need?
How much will I save on my monthly bill?

For businesses, it answers:

What size of solar plant do I need for my factory/office?

Curious about actual installations? Read more at our blog: Things to know before installing solar panels on your roof

Types of Solar Calculators

There are different types of solar cost calculators depending on what you want to know:

For homeowners, it answers:

Solar Rooftop Calculator – Best if you know your roof size and want to see how many panels will fit.
Solar Panel Cost Calculator – solar panel price calculator focuses on price, subsidy, and budget planning.
Solar panels kWh Calculator – Shows how much power (units) your system will generate.
Solar Panel Calculator for Home – A simple version for households with 1–5kW needs.

Factors That Affect Your Solar Calculation

Every home or office is different, and so is every solar estimate. Some things that matter are:

Electricity usage – A family with a ₹5,000 bill needs a bigger system than one with a ₹2,000 bill.
Roof size & shade – A shadow-free roof is perfect; a smaller roof may limit how many panels you can fit.
Panel efficiency – Monocrystalline panels give higher output, while polycrystalline are more budget-friendly.
System type – On-grid systems are cheaper; off-grid and hybrid need batteries, so they cost more.
Government subsidy – Central and state policies can reduce your upfront cost by 20–40%.