Online calculator – calculate instantly in your browser

All calculators in one place

• Basic and scientific functions – sin, cos, tan, logarithms, powers and roots on one keypad.
• Percentage calculator for discounts, changes and proportions with five calculation modes.
• Fractions, equations, derivatives and integrals with step-by-step results to support high school and study.
• Graphing calculator that plots the function's graph and finds the zeros right in your browser.
• Everyday calculators: work hours, salary estimate, character count as pages, download time and net worth.

Browse math calculators Read the user guide

Why use an online calculator?

A physical calculator isn't always at hand, and your phone's built-in calculator only offers basic functions. An online calculator combines the best of both: it opens in a second, shows the whole calculation in writing order, and stores your history so you can return to earlier results. Because all the computing happens in your own browser, results appear instantly with no waiting and your inputs are never sent anywhere.

Laskurikeskus is designed primarily for mobile use. The keys are large enough for touch, the result updates in real time, and every tool fits on a single screen. The same page also scales to the desktop, where you get a wider view and keyboard shortcuts.

Commonly searched calculations on one page

Every day people turn to the web for help with recurring calculations: what a certain percentage of a sum is, how many pages a text takes, how long a file download lasts, or what the sum of fractions is. For all of these there is a dedicated tool here that gives an answer instantly, without memorizing formulas. We gathered the calculators in one place so you don't have to search separate sites for every need.

Every calculator is built to work on its own: it opens quickly, shows the result clearly and in many cases the intermediate steps too. You can add a tool you use often to your browser bookmarks or create a shortcut on your phone's home screen, so the calculator is always one tap away. This makes an online calculator as handy as an app, but without installation or updates.

Works on all devices

Laskurikeskus is designed mobile-first, so the keys are large enough for touch and the result updates in real time. The same page scales to the computer, where a wider view is available. Because the site requires no installation, it always stays up to date without updates, and you can move seamlessly from one tool to another through the same menu.

In summary

Laskurikeskus brings dozens of free calculators together at one address, so everyday and study calculations get done quickly right in your browser. Choose the tool you need, enter the values and read the result – without registration or installation. The computing happens in your own browser, so it is fast and private. Add the page to your bookmarks and the calculators are always within reach on phone and computer. The site works without a separate app, so there is nothing to download or update, and every tool opens ready to use.

Frequently asked questions