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ISO week details

Week 18 1978: May 1–7, 1978

Week 18 starts on Monday, May 1, 1978 and ends on Sunday, May 7, 1978.

Calculate More Dates Open 1978 Week Calendar
Week18
ISO year1978
StartMay 1
EndMay 7

Quick answer

Week 18 of 1978 is the seven-day ISO week from May 1, 1978 to May 7, 1978. ISO weeks always run from Monday to Sunday.

Use week 18 in professional planning

This permanent week reference can be used in project plans, payroll notes, weekly reports, production schedules and deadline documents. Share the week number together with the ISO year and exact date range to avoid ambiguity around New Year.

For calculations that span more than one week, use the weeks between dates calculator. For work schedules, compare the same range with the business days calculator or open the project timeline calculator.

PreviousWeek 17, 1978Apr 24–Apr 30 Year hubAll ISO weeks in 1978Open the complete Monday–Sunday calendar NextWeek 19, 1978May 8–May 14
Nearby references

Weeks around week 18

Week 15, 1978Apr 10–Apr 16 Week 16, 1978Apr 17–Apr 23 Week 17, 1978Apr 24–Apr 30 Week 19, 1978May 8–May 14 Week 20, 1978May 15–May 21 Week 21, 1978May 22–May 28
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FAQ

What are the dates for week 18 of 1978?

The dates are May 1, 1978 through May 7, 1978.

What day does this week start?

It starts on Monday.

What day does this week end?

It ends on Sunday.

How should I write this week in a report?

Use “ISO week 18 of 1978 (May 1–May 7, 1978)” so the week-year and date range are both clear.