The Free Tools Network
ProSolarCalc is one of 66 free tools by Sri Murugan Systems. Every tool runs in your browser, with no account and no paywall. Here are the other 65.
Everyday math and measurement 8
Square Footage Calculator
Area of rooms, floors and walls, including odd shapes.
thesquarefootagecalculator.com Percentage Calculator
Percent of a number, percentage change, discounts and more.
bestpercentagecalculator.net Fraction Calculator
Add, subtract, multiply and divide fractions with every step shown.
fractionsteps.com Tire Size Calculator
Compare two tire sizes: height, width, sidewall and speedometer error.
tiresizecalc.net
Shipping and packing 3
Box Volume Calculator
Volume of boxes, cartons and containers in your chosen units.
boxvolumecalculator.com Girth Calculator
Length plus girth against carrier limits, plus body measurements.
girthcalculator.com Dimensional Weight Calculator
Dimensional (volumetric) weight for courier and parcel shipping.
dimweightcalc.com
Home, construction and energy 13
Concrete Calculator
Concrete volume, cement, sand and aggregate for slabs and footings.
concretematerialcalc.com Construction Calculators
A hub of calculators for building materials and estimates.
constructioncalchq.com Tank Volume Calculator
Volume and fill level of cylindrical, oval and rectangular tanks.
tankvolumecalc.com Solar Battery Bank Calculator
Battery bank sizing for off-grid solar by load and autonomy.
solarbatterybankcalc.com
Money and finance 7
Capital Gains Tax Calculator
US federal, NIIT and state tax on a sale, for 2026 and 2027.
capitalgainshq.com India EMI Calculator
EMIs, total interest and schedules for home, car and personal loans.
indiaemi.com
Tax, pay and benefits 6
VA Disability Calculator
Combined VA disability rating and 2026 monthly pay with dependents.
vadisabilitycalc.net BAH Rate Calculator
Basic Allowance for Housing by duty station, plus military pay tools.
bahratecalc.com Long Service Leave Calculator
Australian long service leave owed and its value, by state Act.
longserviceleave.com Council Tax Calculator
UK council tax for any council and band, monthly and yearly.
counciltaxhq.co.uk