Days Between Dates — calculate the exact interval
How many days are left until an event, or how many have passed since an important date? Enter two dates and get the exact difference in days — handy for countdowns, deadlines or anniversaries. Every calculation stays saved, so you can keep track of more than one at a time without redoing it.
What it records
- What you're counting, e.g. Wedding countdown
How it works
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The app’s source
# 📅 Days Between Dates
How many days are left until an event, or how many have passed since an
important date? Enter two dates and get the exact difference in days —
handy for countdowns, deadlines or anniversaries. Every calculation stays
saved, so you can keep track of more than one at a time without redoing it.
::::form{path="spans" id="fin"}
::input{form="fin" field="label" placeholder="What you're counting, e.g. Wedding countdown"}
::input{form="fin" field="from" type="date" required="true" legend="From"}
::input{form="fin" field="to" type="date" required="true" legend="To"}
::add-form{form="fin" path="spans" label="Calculate"}
::::
:::python{data="spans"}
```
from datetime import date
rows = data["spans"]
for r in rows:
start = date.fromisoformat(r["from"])
end = date.fromisoformat(r["to"])
days = (end - start).days
note = " (in the past)" if days < 0 else ""
print(f"{r['label']}: {days} days{note}")
```
:::
## History
:::table{path="spans" headers="What,From,To" deletable="true" editform="fin"}
{label} | {from} | {to}
:::
Every row stays saved on your device: come back anytime to update the
countdown or check the dates you've already calculated.