How-To Guides
Step-by-step guides that teach you how to perform calculations manually.
How to Calculate Your Conception Date: Step-by-Step Guide
Learn how to calculate your estimated conception date by hand using your last period or due date. Simple formulas, step-by-step examples, and tips included!
Read guideHow to Calculate Your Pregnancy Due Date and Trimester: Step-by-Step Guide
Learn how to manually calculate your pregnancy due date, current gestational week, and trimester using standard clinical guidelines like Naegele's Rule.
Read guideHow to Calculate Target Heart Rate: Step-by-Step Guide
Learn how to calculate your target heart rate zones manually using the clinical Karvonen formula. Includes step-by-step examples and a healthy range chart!
Read guideHow to Calculate Ideal Body Weight: Step-by-Step Guide
Learn how to manually calculate your ideal body weight using the Devine, Robinson, Miller, and Hamwi formulas with our easy, step-by-step guide.
Read guideHow to Calculate Your Daily Protein Needs: A Step-by-Step Guide
Learn how to calculate your daily protein needs and meal-by-meal breakdown by hand with our easy, step-by-step guide and formula.
Read guideHow to Calculate Calories Burned: Step-by-Step Guide
Learn how to calculate calories burned manually using MET values, body weight, and exercise duration with our easy-to-follow, step-by-step guide.
Read guideHow to Calculate BMR: Step-by-Step Guide
Learn how to calculate your Basal Metabolic Rate (BMR) manually using clinical formulas. Step-by-step math, examples, and daily calorie guide included!
Read guideHow to Calculate Body Fat Percentage: Step-by-Step Guide
Learn how to calculate your body fat percentage manually using the trusted US Navy method. Includes formulas, worked examples, and healthy range charts.
Read guideHow to Calculate BMI for Women: Step-by-Step Guide
Learn how to calculate BMI manually for adult women with our easy step-by-step guide. Includes formulas, examples, and healthy range charts!
Read guideHow to Calculate BMI: Step-by-Step Guide
Learn how to calculate your Body Mass Index (BMI) manually using metric or imperial formulas. Includes WHO weight charts, examples, and common mistakes.
Read guideHow to Calculate Your Target Heart Rate Zones: Step-by-Step Guide
Learn how to calculate your personal target heart rate zones using the scientific Karvonen formula. Step-by-step guide with examples and training chart.
Read guideHow to Calculate Sunrise Time: Step-by-Step Guide
Learn how to calculate the exact sunrise time for any location and date by hand using solar declination and hour angle formulas.
Read guideHow to Calculate Time in Decimal Hours: A Step-by-Step Guide
Learn how to convert minutes into decimal hours manually for payroll and billing. Includes a simple formula, worked examples, and common pitfalls to avoid.
Read guideHow to Calculate Time Zone Offsets: Step-by-Step Guide
Learn how to calculate time zone offsets and compare times across the globe manually with our easy, step-by-step guide!
Read guideHow to Calculate Sunset Time Manually: A Step-by-Step Guide
Learn how to calculate the exact sunset time for any location and date by hand using the Sunrise Equation. Step-by-step astronomy math made simple!
Read guideHow to Calculate Solar Noon: A Step-by-Step Guide
Learn how to calculate solar noon manually using longitude and the Equation of Time. Master solar positioning with our easy-to-follow guide.
Read guideHow to Calculate Days to Retirement: Step-by-Step Guide
Learn how to manually calculate the exact number of days, months, and years remaining until your target retirement date with our easy-to-follow guide.
Read guideHow to Calculate the Quarter of the Year: Step-by-Step Guide
Learn how to manually calculate which calendar or fiscal quarter any date falls into, find start/end dates, and calculate days remaining.
Read guideHow to Calculate the ISO Week Number: Step-by-Step Guide
Learn how to calculate the ISO 8601 week number for any date by hand. Step-by-step instructions, formula, worked examples, and common pitfalls explained.
Read guideHow to Convert Hours to Minutes: Step-by-Step Guide
Learn how to easily convert hours to minutes by hand! Follow our simple step-by-step guide with formulas, examples, and common mistakes to avoid.
Read guideHow to Convert Military Time: Step-by-Step Guide
Learn how to easily convert between 12-hour and 24-hour (military) time formats with our friendly step-by-step manual calculation guide!
Read guideHow to Convert Decimal Hours to HH:MM: A Step-by-Step Guide
Learn how to convert decimal time to hours and minutes manually. Perfect for timesheets and billing. Simple, easy-to-follow steps included.
Read guideHow to Calculate Time to Decimal: Step-by-Step Guide
Learn how to convert hours and minutes into decimal format for timesheets and billing. Master the simple math behind the conversion with our easy guide.
Read guideHow to Convert Between Time Units: Step-by-Step Guide
Master time conversions by hand! Learn how to easily convert seconds, minutes, hours, days, and years with simple formulas and friendly examples.
Read guideHow to Calculate Your Exact Age: Step-by-Step Guide
Learn how to calculate your exact age in years, months, days, hours, and minutes by hand with our easy, friendly step-by-step math guide!
Read guideHow to Calculate the Day of the Week: Step-by-Step Guide
Learn how to calculate the day of the week for any date in history by hand using a simple formula. Perfect for students, teachers, and trivia lovers!
Read guideHow to Calculate Days and Business Days Between Dates: A Step-by-Step Guide
Learn how to manually calculate total days, business days, and weekends between any two dates with this easy, step-by-step guide.
Read guideHow to Calculate Target Dates Manually: A Step-by-Step Guide
Learn how to add or subtract days, weeks, and months from any date by hand. Master calendar math, leap years, and days of the week easily!
Read guideHow to Calculate the Difference Between Two Dates: Step-by-Step Guide
Learn how to manually calculate the exact days, weeks, months, and weekdays between any two dates with our easy, step-by-step guide.
Read guideHow to Calculate Your Exact Age by Hand: Step-by-Step Guide
Learn how to calculate your exact age in years, months, days, hours, and minutes manually using our easy step-by-step math guide.
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