Science-Backed Guides on Health, Finance & Everyday Life
18 in-depth articles on sleep science, personal finance, digital wellness, and life productivity. Every article is peer-reviewed, cites its sources, and links to a free interactive calculator.
All Articles
Calorie Deficit Calculator: How Many Calories to Lose Weight? (TDEE & Macros)
Free calorie deficit calculator. Get your personalised TDEE, daily calorie target, full macro breakdown (protein, carbs, fat), and a visual weight loss timeline. Based on the Mifflin-St Jeor equation — the most accurate BMR formula.
Discount Calculator: Percentage Off, Stacked Coupons & Original Price Finder
Free discount calculator with 4 modes: calculate percentage off, stack multiple coupons, find original price from sale price, and build a multi-item cart. Works in any currency with VAT support.
Margin Calculator: Gross Margin, Markup, Net Margin & Break-Even
Free profit margin calculator. Calculate gross margin, markup, net margin, and break-even for any product. Compare against industry benchmarks, analyse 10 products simultaneously, and use reverse mode to find the right selling price.
Cosmic Age Calculator: How Old Are You on Mars, Mercury, Jupiter & Beyond
Discover your age on every planet in the solar system — from Mercury to Neptune. See your age in light-years and as a fraction of the universe's 13.8 billion year history. Free & fun cosmic tool.
Daily Hydration Schedule: Exactly When to Drink Water Today
Not just how much water — exactly when to drink it. Get a personalised hourly drinking schedule based on your weight, wake time, and activity level. Stop guessing about hydration.
Days Until Calculator: Live Countdown to Eid, Christmas & Any Event
Free live countdown calculator. Count exact days, hours, minutes and seconds until Eid, Ramadan, Christmas, New Year, Diwali, birthdays or any custom event. Add multiple simultaneous countdowns.
Deadline Countdown Timer: Live Countdown to Exams, Projects & Submissions
Free live deadline countdown timer. Set multiple deadlines for exams, projects, and submissions. See exact days, hours, minutes and seconds remaining with urgency alerts and progress tracking.
Exact Age Calculator: How Old Are You — Down to the Second?
Free exact age calculator. Find your precise age in years, months, weeks, days, hours, minutes and live seconds. Includes zodiac sign, Chinese zodiac, generation, heartbeats, and next birthday countdown.
Life Progress Bar: See Your Life in Weeks (How Many Are Left?)
A human life is about 4,000 weeks. See your life as a grid of weeks — every filled box is a week you have lived, every empty box is a week still ahead. The most thought-provoking tool you will use today.
Meal Timing Calculator: Exactly When Should You Eat Today?
Free personalised meal timing calculator. Enter your wake time and goal to get exact breakfast, lunch, dinner and snack times. Based on circadian rhythm and chrono-nutrition research.
Number System Converter: Binary, Decimal, Hexadecimal, Octal — All-in-One Guide
Convert between binary, decimal, hexadecimal, and octal instantly. Includes 6 free converters for programmers, students, and web developers. Plus reference tables and step-by-step guides.
Test Grade Calculator: Convert Any Score to Letter Grade (US, UK, Germany, Pakistan, India)
Free test grade calculator. Convert any marks or percentage to US, UK, German, Pakistani, or Indian letter grades instantly. Includes weighted grade calculator, reverse 'what score do I need?' tool, and class average calculator for teachers.
Burnout Risk Calculator — Am I Burned Out? Free 10-Question Test
Take this free science-backed burnout risk assessment. Answer 10 questions about your work, sleep, and stress to get your burnout score and a personalised recovery plan.
Compound Interest Calculator: See Your Money Grow Exponentially
Free compound interest calculator. Enter your principal, rate, and time to see your final balance, total interest earned, and year-by-year growth. Includes monthly contributions and Rule of 72.
How Many Years Has Your Phone Stolen? (Screen Time Calculator)
The average person spends 6+ hours on their phone daily. That adds up to 15+ years over a lifetime. Enter your screen time to see the shocking truth.
How Much Electricity Does an AC Use? (Real Cost Per Month)
Most people have no idea how much their air conditioner really costs. Here is the exact formula, real wattage numbers, and a free calculator to stop guessing.
Inflation Impact Calculator: See How Much Your Money Has Lost
Free inflation impact calculator. See the real purchasing power loss on any amount over any time period using official CPI data. Find what salary you need today to match previous earning power.
Loan EMI Calculator: Calculate Your Monthly Payment & Total Interest
Free loan EMI calculator. Calculate exact monthly EMI for home loan, car loan, or personal loan. See total interest, full amortisation schedule, and how extra payments save you thousands.
Real Hourly Wage Calculator: What Do You Actually Earn Per Hour?
Your salary looks good on paper. But after commute time, work prep, decompression, and job-related expenses — what is your real hourly rate? The answer is always lower than you think.
Salary to Daily Rate Calculator: Convert Annual Salary to Day Rate
Convert any annual, monthly, or hourly salary into a precise daily rate, hourly rate, and contractor equivalent. Essential for freelancers, contractors, and comparing job offers.
Sleep Cycle Calculator — Find Your Perfect Bedtime Tonight
Stop waking up groggy. Calculate your optimal bedtime or wake-up time based on 90-minute sleep cycles. Science-backed, expert-verified, takes 1 minute.
Tip Calculator & Bill Splitter: Split Any Restaurant Bill Fairly
Free tip calculator and bill splitter. Calculate exact tip for any restaurant bill and split it equally or by custom amounts. Works in any currency with country tipping guides.
What If I Invested Calculator: See Your Money's Hidden Potential
See exactly what your daily coffee, subscriptions, or any habit would be worth today if you had invested it instead. Calculate opportunity cost with compound interest, inflation adjustment, and rate comparison.
How We Write CalcPool Articles
Every article on CalcPool is written by a qualified author and reviewed by a scientific expert before publication. We cite peer-reviewed research in every article — not opinion, not hearsay. Our authors include computer scientists, financial analysts, and health researchers. Every article links directly to the interactive calculator it explains, so you can apply the concepts immediately.
New Articles Every Week
We publish new science-backed guides every week. Topics coming soon: compound interest for beginners, the science of motivation, understanding your credit score, and more.