ISO week reference

Week 1 2027: January 4–10, 2027

Exact Monday-to-Sunday dates for 2027-W01. Use this week as a calendar reference, open it in the planner, or view it in the full 2027 ISO calendar.

Plan This Week Open 2027 Calendar

Week1

ISO year2027

Weekdays5

QuarterQ1

ISO reference2027-W01

StartsJan20271, Jan 4

Endsth5154001, Jan 10

Length7 days

Exact dates

Dates in week 1

ISO weeks run Monday through Sunday.

MonJan 42027

TueJan 52027

WedJan 62027

ThuJan 72027

FriJan 82027

SatJan 92027

SunJan 102027

Use this week

Turn these dates into a plan

Open a private weekly planner already set to January 4–10, 2027, then add priorities, deadlines, meetings and hourly work blocks.

Open Week 1 Planner

Year calendarAll 52 ISO weeks in 2027 Quarter viewSee Week 1 inside Q1

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