The Calculator Blog
Learn to master your finances, optimize your home and boost your professional career with our expert guides.
Latest
Health · 5 min read
What is BMI and how to interpret it correctly?
BMI is the world's most widely used weight indicator, but it has limitations worth knowing. We explain what it measures, how to interpret it, and when it is not enough.
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thecalculator.tech
Expert guide
Health
How many calories do I need per day? A guide to BMR and TDEE
Understanding your Basal Metabolic Rate and total energy expenditure is key to losing weight, gaining muscle or staying in shape. We explain it step by step.
28 Jun · 6 min read
Health
How much water should I drink per day? A complete hydration guide
The amount of water you need depends on your weight, activity and climate. We explain how to calculate it, the most common mistakes and tips for staying better hydrated.
28 Jun · 5 min read
Health
Maximum heart rate and training zones: a practical guide
6 min read
Finance
How to Calculate a Mortgage Payment Step by Step
6 min read
Finance
APR vs Nominal Rate: What They Are and Why APR Is What Matters
5 min read
Finance
What Is Compound Interest and How to Grow Your Money
6 min read
Finance
Income Tax in Spain: How Payroll Withholding Is Calculated
5 min read
Finance
Rent or Buy a Home in Spain? The Definitive Guide
7 min read
Finance
Early Mortgage Repayment: How Much Do You Save and When Is It Worth It?
5 min read
Finance
How to Calculate Your Net Salary in Spain: From Gross to Take-Home
5 min read
Finance
VAT Rates in Spain: Standard, Reduced and Super-Reduced
4 min read
Finance
How to Calculate Percentages: The 4 Cases You Need to Master
4 min read
Finance
Personal Loan: How to Compare Offers and Avoid Costly Mistakes
5 min read
Home
The Real Cost of Owning a Car in Spain: Much More Than Petrol
5 min read
Home
How to Reduce Your Electricity Bill: A Practical Guide by Appliance
5 min read
Work
What Is Included in a Severance Payment in Spain and How to Calculate It
5 min read
Work
Self-Employed Contribution 2026: Income Brackets and What's New
5 min read
Work
Unemployment Benefit in Spain: Amount, Duration and How to Apply
5 min read
Work
Retirement Pension in Spain: How It Works and How Much You Will Receive
6 min read
Work
Days Between Dates: How to Count Legal and Employment Deadlines
4 min read
Work
Mandatory Working Time Recording in Spain: What It Is and How to Comply
4 min read
Education
The Pythagorean Theorem: Beyond the Right-Angled Triangle at School
4 min read
Education
Direct and Inverse Rule of Three: When to Use Each with Examples
4 min read
Education
How to Calculate Weighted Grade Average for Master's and Public Exam Applications
4 min read
Education
URM and UARM: Differences, Formulas and Solved Examples
5 min read
Education
Unit Conversion: The Most Common Mistakes and How to Avoid Them
5 min read
Education
How the Spanish DNI letter is calculated (and why it exists)
4 min read
Education
MRUA: what is uniformly accelerated motion and how to calculate it
5 min read