Not everybody is a math whiz. For quick arithmetic, most of us can get away with doing it in our heads. But for serious business and finance reports, having a calculator at your disposal is just a smart decision. Whether you’re studying for the SATs or balancing your check book, a calculator can be invaluable. While we can all use the ones that come on our phones, sometimes that won’t cut it. From calculus to trigonometry to algebra, whether you’re an engineer or a student, calculators come in handy. Make sure your math is never wrong by checking out any of the three calculators we’ve found for you.

Best Financial Calculator

With a lot of programmable features to help customize your usage, the HP 10bII+ Financial Calculator is a great choice for any business or finance professional. It’ll help you easily calculate loan payments, interest rates and conversions. It has over 100 business functions that are simple to access and use. There are more equation functions than a typical calculator, allowing you to quickly figure out standard deviation or cash flows. You can change algorithms while working for a more customized experience. It measures 0.6″ x 3.2″ x 5.7″ so it’ll fit easily on your desk.

Best Scientific Calculator

If you can’t use a graphic calculator for an exam at school, the Texas Instruments TI-36X Pro Engineering/Scientific Calculator is a terrific option. It has multiple different modes, so you can use all the functions that are programmed. There is a MultiView display function that shows multiple calculations on the screen simultaneously. With the MathPrint setting, it’ll show functions, fractions, expressions or symbols stacked as they would appear written down. Perfect for statistics and biology courses, it is solar powered, so you don’t have to worry about changing batteries frequently. It converts fractions, decimals and terms including Pi into alternate representations, giving you more versatility. This calculator can fit easily in a backpack or pocket.

Best Calculator for Home

A solid choice for having a calculator on hand at home, the Helect Standard Function Desktop Calculator has large buttons for simple pushing. It is both solar powered and uses batteries, so it’ll always be working for you. With an on/off button, you can power it down when you don’t need it. It has a 12 digit display and offers you the ability to leave it on the desk and still read it, as it is slanted upward. Whether you’re doing your taxes or just need to figure out some fast math, this will work just fine for you.