Frequently Asked Questions
Everything you need to know about calculating time between dates, live countdowns, and sharing intervals.
The basicsOpen the SpanBetween calculator, set your start date on the left panel and your end date on the right panel, then read the result in the middle. The calculator shows the exact span in days, hours, minutes, and seconds — updated instantly as you change the dates.
You can also switch between display modes using the buttons below the numbers: Days · Hrs · Min · Sec, Hours · Min · Sec, Minutes · Sec, or a single raw seconds readout.
The "Now" toggle pins either the start or end date to the current moment. When active, it turns the display into a live clock that ticks every second.
If "Now" is on the left and you set a future date on the right, you get a countdown — the gap shrinks in real time. If "Now" is on the right and you set a past date on the left, you get a count-up — showing how much time has elapsed since that moment.
Yes. Set your past date on the left panel, then toggle "Now" on the right panel. The display will show how much time has elapsed since your chosen date — counting up every second in days, hours, minutes, and seconds.
This is useful for tracking how long a project has been running, how long since a contract was signed, or how many days since any milestone.
SpanBetween updates every second using your device's local clock. The calculation is precise to the second. For time zones, the dates and times you enter are interpreted in your local time zone — so if you set a target of midnight, it means midnight in your local time.
A countdown measures time remaining until a future event — it shrinks toward zero. A count-up measures time elapsed since a past event — it grows from zero.
SpanBetween handles both. Green numbers indicate a countdown (time remaining). Purple numbers indicate a count-up (time elapsed).
See the live answer on our Days Until Christmas page — it shows the exact countdown to December 25 in days, hours, minutes, and seconds, updated every second.
See the live answer on our Days Until New Year page — it shows the exact countdown to January 1 in days, hours, minutes, and seconds, updated every second.
Yes. Set the start time on the left and your end time on the right — make sure neither is set to "Now" — and the result shows the exact interval. Switch to "Hours · Min · Sec" view for a clean work-duration readout without the days column.
Click the Copy Link button at the bottom of the calculator. This copies a URL that encodes your exact settings — both dates, times, "Now" states, and the active view mode. Anyone who opens the link sees the same configuration.
You can also click Email to open your mail client with a pre-written message containing the dates, current span, and a link back to the live calculator.
Live JavaScript countdowns cannot run inside email clients — Gmail, Outlook, and Apple Mail strip scripts for security reasons. The best approach is to send a clean email with the key details and a link to the live countdown on SpanBetween.
The Email button on the calculator does exactly this: it opens your mail client with the event name, dates, current time remaining, and a direct link to your live interval.
Use the Countdown Designer. You can name your countdown (e.g. "Christmas," "My Wedding," "Product Launch"), choose custom colors from 8 presets or a full color picker, pick a font, and toggle seconds and labels on or off.
The designer generates a self-contained HTML snippet you can paste anywhere, and a shareable link you can send to anyone.
No. All calculations happen locally in your browser. No dates, times, or personal information are sent to any server. Shared links encode everything in the URL itself — nothing is stored on our end.
Ready to calculate?
Open the calculator and find the exact time between any two moments — or build a custom named countdown to share with anyone.