Calculate the exact date 180 days from any start date. Find the half-year mark with milestones, weekly breakdown, and monthly distribution.
The 180-Day Calculator finds the exact calendar date that falls 180 days before or after a starting date. A span of 180 days is close to half a year, so it shows up often in scheduling, deadline tracking, and eligibility windows.
This page gives you the target date along with a breakdown of the period in weeks, hours, minutes, and 30-day checkpoints. That makes it useful when you need to plan around a long interval without counting the days by hand.
Use it for any workflow where a fixed half-year-style offset matters more than a simple month count.
A 180-day span crosses month boundaries and can include leap-day effects, so manual counting is easy to get wrong. This calculator is useful when you want a reliable target date plus a small set of checkpoints for planning around the interval.
Target Date = Start Date ± 180 calendar days Weeks = floor(180 / 7) = 25 weeks, Remainder = 180 mod 7 = 5 days Hours = 180 × 24 = 4,320 Minutes = 180 × 1,440 = 259,200
Result: June 30, 2026 (Tuesday)
Starting January 1, 2026, adding 180 calendar days lands on June 30, 2026. This spans exactly the first half of the year: 31 + 28 + 31 + 30 + 31 + 29 = 180 days.
The Schengen Area\'s 90/180 rule allows short-stay visitors up to 90 days within any rolling 180-day window. Similarly, many countries use 180 days to define tax residency thresholds. Accurately tracking these periods prevents overstays and tax complications.
Securities regulations, insurance claims, and court filing requirements often specify 180-day windows. Missing these deadlines can result in forfeited rights or penalties. The milestone table helps you set intermediate reminders at 30-day intervals.
Medical protocols frequently schedule follow-up appointments at 180 days post-procedure. Post-surgical reviews, medication efficacy checks, and clinical trial endpoints often use this timeframe as a benchmark for patient outcomes.
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Not always. Six calendar months can range from 181 to 184 days depending on which months are involved. 180 days is an approximation of half a year.
Yes. If the 180-day span crosses February in a leap year, the extra day is automatically accounted for.
Many countries use 180 days as the threshold for short-stay versus long-stay status. The Schengen Area 90/180 rule and U.S. substantial-presence test both reference 180-day windows.
This calculator counts calendar days, which is one component of the test. The IRS formula also weights days from prior years, so consult a tax professional for the full calculation.
180 days equals 25 weeks and 5 days. The target date is 5 weekdays ahead of the start date.
No. Day 1 is the day after the start date. Add 1 if you need inclusive counting.