Campaign Monitor countdown timer that stays accurate in every inbox

Use a countdown when the email has a real deadline the reader can miss: a sale that ends, an early-bird price, a registration cutoff, the last day to order for delivery. The timer turns "ends Sunday" into a number that keeps shrinking, and because the GIF is rendered when the email is opened, it is still right on Saturday for someone who opens late.

Do not use one where nothing ends. A fake deadline that resets teaches subscribers to ignore the next one. If you run the same offer every day, a recurring countdown timer that resets on a wall-clock rule, such as "order by 2pm for same-day dispatch", is the honest version. For a one-off sale, see the setup for a flash sale countdown timer email.

An evergreen timer gives every subscriber their own window, for example 48 hours from their first open. flashtimer needs to tell subscribers apart, so the URL carries Campaign Monitor's [email] personalization tag: ?vid=[email]. Campaign Monitor replaces it with the subscriber's address at send time, and flashtimer hashes the value before storing it.

Because the tag has to be substituted, put the snippet somewhere Campaign Monitor personalizes. Campaign Monitor's own docs say the behavioral code block in the builder (Advanced plan) does not support personalization tags, so [email] would arrive unchanged there and everyone would share one countdown. Use the one-click insert or your HTML template instead. More on how this works on the evergreen countdown timer email page.

• Evergreen, starts on open: ?vid=[email], Basic and up.
• Ends on their own date: ?end=[yourfield,fallback=] from a custom date field, Pro and up.
• Fixed: no tag needed, everyone sees the same deadline.

A welcome or post-purchase journey sends each email on a different day for each subscriber, so a fixed deadline would be wrong for most of them. Put an evergreen timer in the journey email and each subscriber's countdown starts when they first open it. That is the setup behind a welcome email discount countdown timer.

If the deadline is stored on the subscriber, such as a trial end or renewal date in a custom field, use a dynamic timer (Pro and up). The embed dialog builds the ?end= tag from your field name in Campaign Monitor's [field,fallback=] form, and each reader counts down to their own date. A missing or past date shows the expired frame, not a wrong countdown.

The timer works in Gmail, Apple Mail, Yahoo, Outlook on the web, Mac and mobile, and any client that shows images. Classic Outlook for Windows (2007–2019, and newer versions with Windows animations turned off) shows only the first frame of a GIF. That frame is the correct time left at the moment of opening; it just does not tick. This is why the text line with the deadline matters.

Apple Mail Privacy Protection pre-fetches images. By default those loads get the live countdown as it stood then; on Pro and up, Apple Mail options can show them a message, your fallback image or nothing instead, so cached opens never show a stale time. Gmail caches images through its proxy, so the timer is served with no-cache headers and a reopen shows the current time.

When time runs out the image switches to your expiry message, or to your own fallback image on Basic and up, so a subscriber who opens next week sees "This offer has ended" instead of 00:00:00 on a dead deal.

If the timer shows the same countdown for everyone, check that [email] survived into the sent email's image URL. If no draft appears in the one-click list, check the client ID matches the client that owns the draft and that the campaign has not already been scheduled or sent.