We’re always working to improve CleverTimer. Our October 9, 2026 update made image generation more efficient for Solid, Square and Arc. With the settings we tested, the server produces smaller GIF files and delivers them sooner. Your countdown stays the same size on screen.
Around 83 percent less server time for Solid and Square. That was the result of our own before-and-after comparison of repeated requests following an initial preparation phase. Square’s GIF file size also fell by around 82 percent. These results apply to the test configuration described below. They do not mean that a newsletter loads proportionally faster.
That means less data to transfer, without making your countdown smaller on screen. This can be useful on slower connections. You do not need to change your existing embed code for this update.
You still have four designs to choose from. Split-Flap, with its flip-board animation, was unchanged in this update.
What this update means for you
- Less image data: Solid, Square and Arc produce smaller GIF files with the tested settings, while staying the same size on screen.
- No code changes needed: Keep your existing embed code. Whether the optimization applies depends on your timer settings.
- Ready sooner on the server: The measured time savings do not guarantee the same reduction in newsletter load time. The connection and email app also play a part.
Less image data. The same display size.
You embed CleverTimer in your newsletter as an animated GIF. When a new image request arrives, the server can calculate the time remaining and deliver the appropriate timer image. Your recipients do not need an extra plugin.
Before the countdown appears, the server has to prepare the image, the file has to be transferred and the email app has to display it. We improved image generation and the way the images are stored as GIFs. Fewer bytes mean less data to transfer. How quickly the timer actually appears still depends on the connection and the email app.
Four timer designs and what they offer
Solid: a simple, uncluttered countdown
Solid displays the time remaining without separate boxes or circles. It works well when your newsletter already has plenty of images and you want the countdown to blend in.
In our server comparison, response time fell from 145.93 to 24.14 milliseconds. The GIF file was around 70 percent smaller. You can find the full test conditions below the tables.
Square: separate fields for each time unit
Square puts days, hours, minutes and seconds in their own fields, making the individual values easy to distinguish.
Square produced the smallest file of the four designs in the standard configuration we tested: 35.59 rather than 202.43 KiB. Server response time fell from 139.48 to 22.62 milliseconds. If keeping image data to a minimum matters to you, this design is worth a look.
Arc: digits with circular arcs
Arc adds circular arcs around the digits, giving the countdown more visual emphasis.
In the controlled server comparison, response time fell from 180.87 to 81.85 milliseconds. The GIF file was around 43 percent smaller. The time saved was much smaller in live use, although the files were smaller there too.
Split-Flap: the flip-board look
Split-Flap changes the digits with a smooth flipping motion. This animation needs more frames than the other three designs. Its file size in the server comparison was 362.68 KiB.
Split-Flap was unchanged in the test and served as a control. The measured response times of 27.97 and 27.20 milliseconds therefore do not demonstrate a new speed improvement.
Choose Split-Flap if the animation matters more to you than keeping the file as small as possible. The design currently supports 480 × 140 pixels and countdowns with fewer than 100 days remaining.
Countdown timer performance in our server comparison
On October 9, 2026, we compared the previous and optimized image generation in a separate test environment on our live server. The timing table shows the median, which represents the middle of the ordered results. We evaluated 120 successful requests for each design and version.
We requested each timer before starting the measurements, then measured the repeated requests that followed. This matters because the first request can require extra preparation time. Those initial requests are not included in the timing results below.
We measured how long it took to generate and fully transfer a timer image within our server test environment. This excludes the journey over the public internet and display in a browser. A GIF was generated for every measured request; the server was not simply returning a previously generated timer image.
Server comparison: response time for repeated requests
Scroll sideways if needed to see all columns.
| Design | Before | After | Time saved |
|---|---|---|---|
| Solid | 145.93 ms | 24.14 ms | 83.46% |
| Square | 139.48 ms | 22.62 ms | 83.78% |
| Arc | 180.87 ms | 81.85 ms | 54.75% |
| Split-Flap | 27.97 ms | 27.20 ms | Unchanged control |
Server comparison: GIF file size
Scroll sideways if needed to see all columns.
| Design | Before | After |
|---|---|---|
| Solid | 181.83 KiB | 53.80 KiB |
| Square | 202.43 KiB | 35.59 KiB |
| Arc | 460.60 KiB | 260.28 KiB |
| Split-Flap | 362.68 KiB | 362.68 KiB |
Test conditions: 960 successful requests after the preparation phase, spread across four comparison runs in alternating order. Images were requested one at a time. We tested 480 × 140 pixels, an opaque background, English labels, standard fonts, no rounded corners and just under 50 hours remaining. File sizes refer to the GIF file without additional compression during transfer. KiB is a unit of file size; 1 KiB equals 1,024 bytes. The comparison ran with limited test resources alongside the live service. It does not show how the system behaves under many simultaneous requests.
We also compared 32 selected image pairs from the previous and updated versions. Image content, dimensions and animation timing matched in each pair.
What we measured in everyday use
Settings and server load vary in everyday use. We therefore also examined actual timer requests before and after the update. The “Timers” column counts distinct timers for each design, not requests. For images generated repeatedly, we observed the following results:
Observations from the live service
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| Design | Timers | Server-side GIF generation before → after |
|---|---|---|
| Solid | 12× | 132.87 → 66.54 ms |
| Square | 12× | 135.67 → 68.08 ms |
| Arc | 14× | 160.69 → 151.26 ms |
| Split-Flap | 4× | 10.65 → 12.10 ms |
For this comparison, we evaluated timer requests over two 30-minute periods, one before and one after the update. First, we calculated the median generation time for each timer, then the median of those results for each design. The times include any waiting time on the server. Operating conditions differed between the two windows. Unlike the controlled comparison above, these differences may also have affected the results. Browser load times were not measured.
Generation time roughly halved for Solid and Square in this sample. The improvement was smaller for Arc. Split-Flap took slightly longer after the update in this small sample. Its image generation was unchanged and operating conditions varied, so this alone does not establish either an improvement or a deterioration caused by the update.
Not every request needs a newly generated timer image. When an existing image can be reused, faster image generation adds little benefit. The slowest generation cases did not improve across the board either.
Server time and browser load time are different measurements
A server time of 24 milliseconds does not mean your timer appears in a newsletter after 24 milliseconds. Internet transfer and processing by the email provider and email app add to that time. Even a browser download does not tell you when an image will appear in an email.
For this update, we do not have a comparable before-and-after measurement of full browser or newsletter load time. We therefore do not claim a speed-up factor for either. What the comparison demonstrates is lower server times under the stated conditions and smaller GIF files.
When the optimization applies
Optimized image generation currently supports the following settings for Solid, Square and Arc: 480 × 140 pixels, an opaque background, no rounded corners, supported standard fonts, all four time units visible and fewer than 100 days remaining. It is not currently used when the fallback display for Apple Mail is enabled. The benefit depends on the configuration and request; the percentages above apply only to the test described here.
You can still use other available settings. The measured benefits do not automatically apply to them, however. The first request can also take longer than the repeated requests in the comparison. With Split-Flap, the image may be temporarily unavailable during its initial preparation.
Choose your settings to suit your newsletter and the email apps your audience uses. Do not switch off a useful Apple Mail fallback just to improve a test result.
For more detail, read our guide to Apple Mail Privacy Protection and countdown timers.
Frequently asked questions about countdown timer performance
In the server benchmark described here, Square had the smallest file at 35.59 KiB. This applies to the standard configuration we tested. Different colors, fonts, remaining times and settings can produce different file sizes.
Under the tested conditions, the server can make the image available sooner. Transfer and processing in the email app still happen before it appears in the newsletter. An 83 percent reduction in server time therefore does not imply an 83 percent reduction in newsletter load time.
No. You can keep your existing embed code. Whether your timer uses optimized image generation depends on its settings and whether the initial preparation is complete.
The 32 image pairs we checked were identical down to the pixel. Animation length and timing were also preserved. We tested selected configurations, not every possible setting or email app.
No. Email apps and email providers’ image services may reuse a GIF they loaded earlier. The GIF animation does not recalculate the time remaining itself. Include the deadline as regular text and check which fallback display is appropriate for Apple Mail.
How to use the improvements in your newsletter
If you already use a CleverTimer in your emails, you can keep your existing embed code. For a new countdown, choose the design, adjust the colors and labels, and set the end date, time and time zone.
Then copy the generated HTML code into your email tool, keeping the original CleverTimer image URL. If you download the GIF and upload it to your own email platform, later requests will no longer reach CleverTimer to retrieve an image showing the updated time remaining.
For the steps in your email platform, see the relevant guide:
- How to add a countdown timer in Mailchimp
- How to add a countdown timer in Brevo
- How to add a countdown timer in CleverReach
- How to add a countdown timer in Klaviyo
Before sending your campaign, send a test email and check the countdown on both a phone and a computer. Include the end date and time as regular text too: images can be blocked or cached. Apple Mail Privacy Protection may load them before the email is read. A suitable fallback display can help, but detection is not perfect.
A countdown puts your offer in focus and gives your subscribers a clear reason to act before the deadline. This performance test did not measure its effect on clicks or purchases.
For tips on placement and use, see our guide to email countdown timers.