5 tips for using captions in video ads

Webster West · Oct 19, 2022 · 15 min read

Most video ads on social media sites like Facebook and Instagram are watched with sound off by default. This lack of an audio pathway can make messaging very challenging. That’s why captions are so incredibly important when creating video ads for social media. Designers must assume that the entire content of a video ad will be consumed by reading its text captions. In this blog post, a few tips for how best to use captions to message within a video ad will be discussed. This will be supplemented with a discussion of how to apply these tips with the Movidmo video editor which serves as a video ad maker that offers an incredible amount of control over captioning a video ad.

Tip 1: Get the right words

One of the most common mistakes in captioning video ads is having captions that are too long. Long captions are sometimes displayed in a very small area so as not to completely cover the remainder of the video design. A smaller display area, however, can greatly reduce legibility. The goal is to not frustrate the viewer with captions that require eye strain when viewing the ad. For this reason, the Movidmo video editor provides a warning when a caption exceeds a certain number of characters.

In general, long captions reduce design quality. A good video ad design needs to be well balanced between words and other design elements like media, shapes and icons. Product imagery is oftentimes as important or even more important than the caption text. Too many words leads to a Powerpoint look. A well designed ad should not look like a converted Powerpoint presentation. For this reason, a good strategy is to cleverly break one or two messaging statements into captions to be displayed across multiple scenes within the video ad. When developing the messaging, try to say what needs to be said in as few words as possible. Spend time word smithing the overall messaging before trying to break it into captions.

As a simple example, consider the Welcome Fall video ad template from the Movidmo template library as shown below. The core messaging for this video ad is made up of the statement “Welcome Fall with 30% off.” The messaging was divided into two sets of captions.The first says “Welcome Fall” and the second says “With 30% off”. This video ad also has a call to action after this messaging that features a web address as a caption. Of course, all of this content is editable within the Movidmo editor.

Tip 2: Get the timing right

The mistake of a caption that is too long is oftentimes compounded when the caption is not displayed long enough so that it can be easily read by the viewer. Of course, the opposite problem where a short caption is displayed for too long can also be problematic. This typically results in a bored viewer, and bored viewers scroll away leaving the video ad behind. If an error is to be made, however, it is probably best to display a caption a little longer than necessary rather than for less time than needed for reading. Getting display time correct depends on the length of the caption. It really boils down to computing the number of words in a caption per second of display time. As a general rule, humans can read about two or three words per second. To be conservative, this means two to three words can be added to a caption for every one second of display time. If there are other important items being displayed in the video ad at the same time, the display time of the caption may need to be extended to give the viewer time to consume all of the visual content.

For the Welcome Fall video ad template, “Welcome Fall” is displayed for two seconds, and “With 30% off” is displayed for three seconds. This rather generous time allotment for the caption content is to allow the viewer to also enjoy the accompanying video of beautiful Fall foliage that provides the setting for the ad.

Captions that are displayed in the introductory seconds of a video ad can be particularly problematic. If the video starts playing before the viewer has a chance to completely scroll the ad into view and focus on its content, important messaging in the video ad may be overlooked. For this reason, it’s a good idea to pad the display times of introductory captions with a few seconds or to delay their display to a second or two into the video ad.

When it comes to display time, every decision has to be balanced with the optimal length of the video ad as a whole. Every second matters as viewers will be lost for each additional second added to the duration of the ad. It is recommended that the length of an ad be somewhere between 10 and 30 seconds, so keep this guideline in mind when developing a strategy for the timing of captions.

Tip 3: Style matters

The styling with which captions are displayed can also have a tremendous impact on the effectiveness of the messaging in a video ad. A common mistake is to display the messaging in a particular scene as a single caption on one horizontal line. This approach to messaging leads to the Powerpoint vibe for a video ad. If Movidmo is used as the video ad maker, captions can be resized so that they appear across multiple lines. The standard line spacing for many fonts may seem a little excessive. When editing a caption in the Movidmo editor, the line height can be reduced for a more compact display by changing the default Auto setting to a value less than 100%.

Perhaps the most important design suggestion for captioning video ads is to use separate fonts for each line of a multi line caption. In the Movidmo editor, this approach requires separate caption elements for each line which has other benefits that will be discussed below when it comes to effects. For the headline caption, choose an attention grabbing font and pair that with a more standard font for supplementary captions.

Pairing fonts is a nontrivial task where more design experience may be helpful. One simple piece of advice is to pair serif and sans-serif fonts. Serifs are the small details that extend along the edges of letters in a typeface. Serif fonts have these details while sans-serif fonts do not. A few examples of serif fonts that are available in Movidmo are Arvo, Graduate and Playfair Display. A few examples of sans-serif fonts available in Movidmo are Lato, Montserrat and Roboto. It’s amazing how different font combinations provide a different feel for a video ad, so it is always a good idea to try a few combinations to see which one best matches the desired mood for the ad.

With the Welcome Fall video ad template, the messaging in each scene is split into two captions. Within each scene, the smaller top caption is displayed in the Ubuntu font and the larger bottom caption is displayed in the Anton font. These fonts were chosen because the two fonts can be easily differentiated. Ubuntu is a standard width and height font whereas Anton is a tall skinny font.

In addition to choosing different typefaces for a multi line set of captions, consider also changing other stylistic features of each caption. Headline captions may best appear in bold and/or be significantly larger than the lines below it. When varying font size, it is important for the font sizes to be very different or otherwise the human eye will want to make them the same. Font sizes that are too close are a big design no no as they tend to be visually confusing. For the Welcome Fall video ad template, the top caption in each scene is a size 48 point font and the point size of the bottom caption is larger than 150 in each scene.

Whether or not a caption should appear in all caps is a difficult question to answer. All caps may look great for a shorter caption, but no one wants to read more than just a few words in all capital letters. In general, capitalization can be used to assign importance to certain captions in a manner similar to bolding the font. For the Welcome Fall video ad template, the top caption in each scene only capitalizes the first letter whereas the bottom caption receives more attention by appearing in all caps.

Changing other features such as the text and background colors of each caption line should also be considered. One simple approach is to invert the color scheme for each line by swapping the text and background colors for the captions that make up each line. If a caption spans more than two or more lines, also consider making the background color transparent for each caption and then add a shape as a common background to the entire multi line sequence. A variety of interesting shapes are available in the Movidmo editor and applying interesting shapes as backgrounds for captions can make a video ad have a much more professional feel.

One may also consider having completely transparent backgrounds for captions as is the case with the Welcome Fall video template. This approach can provide a more immersive feeling where the caption text folds into the background content. Keep in mind that for text with a transparent background to be more legible, it typically needs to be displayed in a larger font size with a color that does not meld into the background.

One last idea when it comes to styling captions is to consider using a different letter spacing than what is provided by default for a particular font. In the Movidmo editor, letter spacing may be defined as Auto meaning the default letter spacing for the font is to be used, or it may be explicitly defined as a number with 0 representing no space between letters. Negative values make consecutive letters overlap. This can sometimes be used to create a playful vibe for a video ad. Increasing the letter spacing above 0 can provide a more dramatic feel to the caption text as the letters will be further apart. One particularly good design tip is to increase the letter spacing for captions that contain web addresses, phone numbers or other text content that is not made up of actual words. Increased letter spacing makes this content much more legible as the viewer can more easily spell it out. As an example, the letter spacing for the Web address in the Welcome Fall video ad template is set to 5.

Tip 4: Movement matters

Entry and exit effects can be used to signal the viewer that important information is entering or leaving a video ad. This signaling is particularly important for captions to draw the viewer’s eye to the vital messaging content that they contain. Entry and exit effects also have a huge impact on the energy of a video ad. The type of effect as well as the speed with which the effect is completed both contribute to this energy factor.

Movidmo provides more than 80 effects for captions. These range from basic slide and reveal effects to forceful stomp effects and flashy pizzazz effects. Simply specify the type of effect and the second in the video ad where the caption is to enter or exit. In addition to these properties, the speed and delay to be applied to the effect can also be specified. Speed is specified as the time to completion for the effect in quarter second intervals ranging from 0.25 seconds to one full second. The same range goes for the delay time with the total of the completion time and delay time for the effect being restricted to one second or less.

There are a few thoughts to keep in mind when applying effects to multi line captions in a video ad. Applying the same effect to each caption is almost never the right idea. Instead, try using a more splashy effect for the larger caption and more subdued effects for the captions around it. In terms of the timing of entry effects, the effects can occur at the same time for each caption, or the top/bottom caption can enter first followed by staggered entry for the other captions. This staggered approach defines a nice ordering that increases readability for the viewer. If the messaging in a video ad is broken out as several multi line captions spread out across several scenes as suggested above, then it is also a good idea to apply the same effect scheme to the captions in each scene if possible. A viewer can quickly adapt to the pattern and more easily digest the information being conveyed from scene to scene. This consistent approach is particularly helpful when each set of captions are in approximately the same physical location within each scene.

Each scene in the Welcome Fall video ad template features the top caption entering by growing to the bottom right corner of its container and the bottom caption growing to the top left corner of its container. These two entry effects make for a nice complimentary combination as the two captions grow together. The captions in each scene also occupy roughly the same physical position in the video.

Tip 5: Be decorative

This last tip is not so much about the properties of a video ad caption itself as it is about what is going on around it. Once a caption enters a video ad, the viewer’s eye may be drawn away to other content like an image or a video in the ad. Decorative elements displayed around a caption can be used to subtly draw the viewer back to the important messaging in a caption.

When using Movidmo to make a video ad, this can easily be accomplished by adding shapes around the caption content. Decorative shapes like line segments, corners and rectangular frames can be used as outlines to draw the focus back to a caption. Also, any of the large variety of star-like shapes that Movidmo provides can be used to accentuate captions. The decorative effect can be multiplied by applying interesting effects with a decorative shape repeatedly over the period of time that a caption is displayed in the video ad. In the Welcome Fall video ad template, an underlying wiggle segment is used to define the bottom caption after it appears in each scene.


The tips above are by no means exhaustive when it comes to the design considerations associated with captioning a video ad, but they are a start. When making a Facebook video ad, an Instagram video ad or a video ad for some other platform, these tips should prove helpful. Always experiment with different ideas and don’t be afraid to look around for outside sources of design inspiration. The Movidmo template library is always a good place to start if you are looking for ideas or for a video ad maker. Use the Contact Us link at the top and bottom of this page to pass along caption design ideas to the Movidmo team.