180 Days Ago

Unspool the Rewind Ribbon

The ribbon runs from today (right) backward to the target date (left), with month markers for every calendar month it crosses.

Common Look-Back Windows

Standard compliance and notice windows, one tap each.

Days-Ago Conversion Table

Looking forward instead? Try the 180 days from today calculator.

The Rewind Formula

180-Day Windows in Regulation

No saved look-backs yet. Tap "Save to History" to remember up to six rewind calculations.

How to Find the Date 180 Days Ago

1. Leave the reference date as today, or set it to a deadline you need to count back from.
2. Confirm the look-back is 180 days (the half-year preset), or drag the slider to 30, 90, or 365 days.
3. Watch the rewind ribbon unspool backward and stamp the target date at its left end.
4. Compare against the six-calendar-month figure shown in the result card — they can differ by a few days, and the rule you are following decides which to use.
5. Save the result to local history for your audit trail or compliance log.

The 180-Day Window Explained

In 2026, a compliance officer auditing a 180-day SLA breach window, a product recall coordinator tracing every unit shipped in the last six months, or a renter who must prove a 180-day continuous-occupancy claim, all need the same single fact: what calendar date fell exactly 180 days before today? This tool answers that by unspooling a half-year rewind ribbon backward from today, stamping the target date where the ribbon ends. 180 days is the canonical half-year look-back window, and getting it off by even a day can invalidate a claim.

The 180-day window is everywhere in modern policy because it is the cleanest approximation of half a year. A full year is 365.2422 days, so a precise half is 182.6 days, but regulators and contracts overwhelmingly round to 180 — exactly six 30-day blocks — because it is memorable and computes without fractions. The US Securities and Exchange Commission's Rule 144 holding period, many insurance pre-existing-condition look-backs, passport six-month validity rules, and standard commercial recall windows all use either 180 days or six calendar months, and the two are not identical.

The distinction between 180 days and six calendar months matters more than people expect. Six calendar months back from 31 August is 28 February (or 29 in a leap year) — a span of 184 days. But 180 days back from 31 August is 4 March, four days later. Whenever a rule says "180 days" rather than "six months," you must count days, not months, which is exactly what the rewind ribbon does: it subtracts a fixed 180 days regardless of month lengths, then shows you the resulting date.

Counting days backward across month boundaries is where manual math fails. Going back through February — 28 days in a common year, 29 in a leap year — shifts every earlier result by a day depending on the year. The Gregorian leap rule, set by Pope Gregory XIII's 1582 reform of Julius Caesar's Julian calendar, adds 29 February in years divisible by 4 except centuries not divisible by 400. A 180-day rewind that crosses 29 February in a leap year lands one day earlier than the same rewind in a common year, a subtlety this tool handles automatically.

The phrase "180-day notice" appears throughout employment and tenancy law as a long-form protection period. Some US states require 180 days notice before a mobile-home park closure; the federal WARN Act uses 60 days for mass layoffs but many executive contracts stipulate 180-day non-compete or garden-leave windows. Counting the notice backward — "was the notice served at least 180 days before the effective date?" — is the reverse of the forward calculation and is exactly what auditors verify with a rewind like this.

Recall and traceability rules lean on the 180-day look-back heavily. The US FDA's Food Safety Modernization Act and the Reportable Food Registry expect manufacturers to trace product one step forward and one step back; many internal quality systems set a 180-day batch-trace window. When a contamination is found today, the first question is "what was being produced 180 days ago, and is that lot still in the field?" The rewind ribbon turns that into a one-tap lookup with the exact production-window start date stamped.

For everyday use the workflow is simple: the tool defaults the reference point to today and the look-back to 180 days, then shows the result date, the weekday it fell on, and how that compares to a clean six-calendar-month subtraction. You can change the reference date to back-date from a future deadline, switch the look-back to 90, 30, or 365 days, and save the result. Pair it with the sibling 90-days-ago and 1-year-ago tools and the day counter to map an entire compliance calendar.