Weeks to Days Converter

Chronometry & Gestational Metrology (ISO 8601 & Obstetric Standards)

The week (wk) and day (d) maintain an invariant integer constant:

• **

• Exact Defining Invariant**:

1 Week 7 Days = 168 Hours = 10,080 Minutes

Days = Weeks × 7, Weeks = Days7

• **

• Obstetric Pregnancy Milestones**:

• Full-Term Gestation: 40 Weeks = 280 Days = 9.20 Calendar Months

• 1st Trimester: 12 Weeks = 84 Days

• 2nd Trimester: 27 Weeks = 189 Days

• 3rd Trimester: 40 Weeks = 280 Days

• **

• Standard Project & Calendar Benchmarks**:

• 1.0 Week = 7.00 Days = 5.0 Workdays = 168.0 Hours

• 2.0 Weeks (Fortnight) = 14.00 Days = 10.0 Workdays = 336.0 Hours

• 4.0 Weeks = 28.00 Days = 20.0 Workdays = 672.0 Hours

• 52.0 Weeks = 364.00 Days = 260.0 Workdays

How to Use This Calculator

Enter your Time Value to Convert (e.g. 40), Conversion Direction — choose from Weeks to Days (days = weeks × 7), Days to Weeks (weeks = days ÷ 7), and Pregnancy & Project Benchmark — choose from Custom Time Value, 40.0 Weeks (Full-Term Pregnancy Gestation) → 280.00 Days (6,720 Hours), 2.0 Weeks (Fortnight / Agile Sprint) → 14.00 Days (10 Business Workdays). Results update instantly as you type — adjust any value to compare scenarios.

The Formula

Formula Reference: Weeks to Days Converter

Input variables:

timeQuantityInput — Time Value to Convert

conversionDirectionSelect — Conversion Direction

Computed outputs:

convertedPrimaryResult — Converted Primary Output

weeksAndDaysDecomposition — Weeks and Days Breakdown (wks + days)

businessWorkdaysEquivalent — Standard Business Workdays (5-day week)

totalHoursEquivalent — Total Hours (hrs)

calendarMonthsEquivalent — Mean Calendar Months (30.44 d/mo)

Mathematical relationships extracted from calculation logic:

days = weeks * 7.0

remDays = (weeks - wholeWeeks) * 7.0

workdays = weeks * 5.0

hours = days * 24.0

months = days / 30.4375

Standard: NIST Handbook 44 and BIPM SI unit definitions

Worked Example

An agile scrum master scheduling a 2-week sprint converts the timeline to 2 × 7 = 14.00 calendar days (10 business working days or 80 work hours per developer).

Understanding Your Result

Unit conversion precision: round to the same number of significant figures as your original measurement. Converting 6 feet to meters gives 1.8288 m — but if your measurement was approximate (±1 inch), expressing more than 2 decimal places is false precision. For international trade and technical specifications, SI units (meters, kilograms, liters) are the standard. US customary units (feet, pounds, gallons) differ from Imperial UK units: 1 US gallon = 3.785 L vs. 1 UK gallon = 4.546 L.