How to add a countdown timer to a Klaviyo email

Published September 26, 2026 · Klaviyo steps checked against its help center on September 26, 2026

Klaviyo has no built-in countdown timer, and its own help center says to use a third-party timer pasted into an HTML block. This guide does exactly that with a DynaMail timer: build it, paste one image tag, and check it with a real profile before you send.

Countdown timer rendered by DynaMail: cards showing days, hours, minutes and seconds remaining — An example render from DynaMail’s image pipeline. Your design, dates and values will differ.

What you need

A DynaMail countdown timer. The free countdown generator makes one without an account; a free account lets you change the date and design later.
Permission to edit a Klaviyo template, an unsent campaign or a flow email.

Add the timer, step by step

1
Build the timer and copy its image tag
Set the end date and timezone in the generator (or the DynaMail dashboard) and copy the snippet. It is one image tag, with your own widget id in place of YOUR-WIDGET-ID:
Countdown timer for a Klaviyo HTML block
```
<img src="https://img.dynamail.io/widgets/YOUR-WIDGET-ID/render.gif" alt="Time left in the sale" width="600" height="196" style="display:block;border:0;" />
```
Open the email in Klaviyo
Klaviyo’s countdown article says to open any existing email: a template, an unsent campaign or a flow email.
Add an HTML block and paste the tag
Add an HTML block where the timer should appear, delete any code already in it, paste the tag, then click the back arrow to apply the change. Klaviyo’s editor guide describes the HTML block as the place for “third-party features like countdown timers”.
Preview with a real profile, then send yourself a test
Klaviyo recommends previewing with a real profile so personalization renders, and notes that some dynamic content behaves differently in a live send than in a preview. Send a live test to your own inbox to see the timer exactly as a subscriber will.

Optional: count unique opens

DynaMail counts unique opens when the image URL carries a recipient identifier in r=. In Klaviyo that is {{ email|urlencode }}: the email address, passed through Klaviyo’s documented urlencode filter so characters such as + survive the query string. DynaMail stores a salted hash of it, not the address.

The same timer with open tracking

<img src="https://img.dynamail.io/widgets/YOUR-WIDGET-ID/render.gif?r={{ email|urlencode }}" alt="Time left in the sale" width="600" height="196" style="display:block;border:0;" />

What subscribers will see

Most inboxes: the time remaining when the image was requested, ticking down for the length of the animation.
Apple Mail: Klaviyo’s article warns that timers may look wrong because Apple Mail can load images before the email is opened. The image then shows the time as of that earlier fetch. Our Apple Mail Privacy Protection explainer covers what that means.
Older Outlook: Klaviyo notes that Outlook 2007, 2010 and 2013 show only the first frame of a GIF. That frame is still the correct time remaining, as our Outlook post explains.
After the deadline: the timer stops at zero rather than counting into negative time.

Sending the timer in a flow, where every recipient should get their own deadline? Follow the evergreen countdown guide for Klaviyo flows. Klaviyo’s own instructions are in its countdown timer article (opens in a new tab).

Sources

Every Klaviyo step above comes from these pages, read on September 26, 2026. Apps rename menus often; if a step no longer matches what you see, the source page is the place to check.

Frequently asked questions

Does Klaviyo have a built-in countdown timer?

No. Klaviyo’s help center says it does not have a built-in countdown timer feature and that you need a third-party tool. The timer goes in an HTML block as an image tag.

Can I use a Klaviyo image block instead of an HTML block?

Klaviyo’s documented method for timers is the HTML block. Its image block can import an image from a URL, but Klaviyo does not say whether that keeps the link or copies the file; a copied file would freeze the timer, so use the HTML block.

Will the timer tick in Outlook?

The timer is an animated GIF. Classic Outlook for Windows can show only the first frame, which still shows the time remaining when the image was fetched; it just does not tick. Every other part of the email is unaffected.

Does the same timer work in a flow email?

Yes. Klaviyo’s countdown article applies to templates, campaigns and flow emails alike. If each person in a flow needs their own deadline, see the evergreen countdown guide for Klaviyo flows.