Addition.site is your go-to collection of easy-to-use online calculators for education and finance needs. Our library includes tools for loan interest, BMI & fitness, pregnancy, and everyday measurements such as distance, volume, and mass. Whether you're a student, teacher, accountant or someone planning for the future, our clear, accurate calculators help you make fast, confident decisions.
We also publish practical guides and how-to articles that explain how calculators work and how to interpret results — perfect for learning and classroom use. Popular calculators on the site include:
If you can’t find a calculator to suit your needs, we’ll make it!
Use our contact form to request custom calculators built for specific tasks or classroom activities.
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