How Many PowerPoint Slides Does a Presentation Need?

Maybe you’ve been in this situation: A colleague is giving a presentation. While he’s talking, you’re shown a huge number of slides; the information literally flies past you. While you’re still thinking about the third slide, he’s already moved on to slide seventeen. Or vice versa: A 60-minute presentation is supported by a few short slides. It’s difficult to follow the presentation and keep track of information because there is basically no visual support.

Neither of these two presentations makes much of an impact. And the presenter doesn’t necessarily do himself any favors either. This shows that choosing the right number of slides in presentations is pretty important.

Presenting with PowerPoint: How many slides are ideal?

First of all: there’s no magic number. Nobody can tell you, “A new slide every two minutes is the secret to success.”  Every presentation is unique. Every presenter has his or her own goals and needs. And, every presentation situation is different.

So, although it’s ultimately up to you to decide on the right number of slides for your presentation, there are a few guidelines you can follow.

Seven rules for choosing the right number of slides for your presentations

1. Quality over quantity

   A wealth of detailed information can impress people, but also overwhelm and bore them. Stick to your key points without getting bogged down in details. You can always take the time to clarify any ambiguities.

Presentation slides should never be a constant flow of data and text. Your audience should be listening to you, not reading. When everything you say is also presented on your slides, it becomes pretty redundant.

A good presentation slide should provide an overview of the key points or augment them with audio-visual material. It should support the presentation, not become it. Keep it clear and brief.

2. Portion out your information

We’ve become used to everything coming to us quickly and automatically. But communicating information doesn’t always work like that. Compare it to a good meal. Instead of piling it all up and eating it in one bite, savoring every bite is a much more enjoyable experience.

And that’s exactly how you should communicate information during your presentation. It’s “more appetizing” and “easier to swallow” for the listener if it’s portioned out. Just because you have enough space on a slide for several important points doesn’t mean you have to use them all. Distribute important points over several slides to emphasize their importance and focus the audience’s attention on them.

For example, if you are referring to a product range, don’t list product A, product B and product C on one slide, but create a single slide for each. These can then be enhanced with pictures or keywords. This of course increases the number of your presentation slides, but it maximizes their impact.

3. As much as necessary, but as little as possible

This is where efficiency really comes into play. It’s all about making sensible cuts. Slides can and should support a presentation. They can provide a guideline, provide additional visual information or simply relax the presentation a bit. As already mentioned, text should not play too much of a role on your slides.

Always question the purpose of material, such as pictures or graphics, and how useful they are for your presentation. Ger rid of anything that seems superfluous or unnecessary or that can be communicated verbally.

What is useful and what can be cut is of course up to you to decide! Although a cartoon or caricature might not be relevant to your topic, it could be a fun way to loosen things up.

Also keep in mind that the number and detail of your slides will affect hoe flexible you can be during the presentation. You are locked into your slides and their content, and the more of them you have, the less chance you have to diverge from them. This can help if you are feeling a little shaky or nervous. But keep this in mind if you’re someone who likes a bit of leeway and to talk freely.

4. Practice makes perfect!

We love telling kids to practice things they don’t feel confident about. So why don’t we that ourselves? A great way to see if a presentation works is to run through it at least once in advance – kind of like a dress rehearsal.

Doing this in front of friends or family can provide you with valuable feedback. But even alone in front of a mirror or with an imaginary audience can work. You’ll quickly see where the problems lie, whether you have enough time and whether the slides fit into the presentation.

If you find that your presentation is finished faster than planned, you can add additional information and slides. If, on the other hand, you had problems completing the presentation within the allotted time and couldn’t discuss individual slides or had to skip them, it’s time to make some cuts.

Naturally, the pace at which you speak plays a big role. Those who speak quickly can cover lots of slides in a short time. If you speak slowly, you will of course achieve less. Ideally, you should speak at a pace that is comfortable for the listeners and allows them to follow the presentation. Again, this takes practice! No matter how quickly or slowly you speak, you should be able to present your slides comfortably.

5. Less is more

Some presenters like to keep a few slides “on ice” just in case there is time left or they feel they haven’t covered everything. This is an option but not really recommended. If the extra slides in your presentation are skipped over, the audience can easily feel that you’re cutting things short and they’re missing something that may be important.

On the other hand, there are also presenters who opt for a minimalist approach to their slides to allow for flexibility or to simplify their presentation. Even this can be irritating or distracting to the audience, as they’re not getting enough visual content.

There should be neither too many nor too few slides. Obviously, this is easier said than done. What is important and what is unimportant, what is helpful and what impedes your presentation is ultimately your decision. Trust your instincts and rely on your expertise.

6. There’s always an x factor!

Another reason why there is no patent solution for the perfect presentation is that there are so many variables that can affect a presentation. Factors such as topic, audience and location should always be taken into consideration when it comes to the scope and structure of slide presentations.

Things to keep in mind:

• The topic. The number of slides that are required and helpful in presentations depends greatly on the topic. For example, pictures or graphics are best suited if you want to explain technical processes, discuss building progress or new products, or present business figures and statistics. It makes little sense to cut down on relevant content just to keep the number of slides low. If your topic is a bit dry, visual material can help keep your audience interested. If your topic relies more on verbal explanations and your slides are there to provide some visual guidance, it wouldn’t make sense to add slides.
• The audience. Who your audience is plays a factor in how many slides you need. Here’s an example: You probably won’t need slides that explain and illustrate technical terms when presenting to an audience of experts in that field. But, if you’re communicating the same content to non-experts or an inexperienced audience, you will definitely need the visual material to clarify and simplify these same technical terms.

The room. The best presentation slide is not worth much if the audience can’t see it. Bad lighting an/or poor sight lines may prevent important content from being effectively communicated. This can be frustrating for both you and your audience. If you know the room isn’t well let or half your audience may not be able to see your presentation, think about investing less work in the slides and focusing more on the oral presentation. On the other hand, a room that offers excellent technical equipment can be a major asset, allowing you to add more audio-visual material, such as background music, to your presentation.

7. Trust your own expertise!

This point summarizes something fundamental; opinions are everywhere. Even something as seemingly innocuous as the optimal number of slides for a presentation is open for debate.  There’s a wealth of advice from experts on how many slides are right for presentations.

Don’t forget that none of these expert opinions were formed with your exact presentation style and topic in mind. And the recommendations often vary widely. While some recommend 40 slides in ten minutes, others recommend just two slides in ten minutes. In the end, you are the expert; you know how many slides you need.

This also applies to the time spent on each slide during the presentation. Not all slides are created equal – some need less time, some need more. It always depends on the structure and content of the slide. Don’t worry if you spend several minutes on one slide, but only seconds on another – that’s perfectly fine.

Expert opinions: helpful, but not mandatory

You can of course reference well-known presentation methods if you feel more confident using a given guideline. But make sure it fits and works with your presentation. Here are some well-known methods for slide presentations:

10/20/30 – The Kawasaki method:

Perhaps the best known and most commonly used method is the 10/20/30 rule by Guy Kawasaki. It specifies that ten slides be used in a 20-minute presentation. A font size of at least 30 should be used for text. This equals to about two minutes per slide – a standard rule for presentations. This method can be great for beginners or inexperienced speakers. However, it’s not an iron-clad rule and can be adapted to fit your needs.

The Pecha Kucha method:

The Pecha Kucha method is becoming more popular. The method comes from Japan and translates to “constantly talking”. Pecha Kucha is based on very rigid guidelines regarding time and the number of slides. A Pecha Kucha presentation contains 20 images. Each image is shown for exactly 20 seconds. The speaking time amounts to exactly 6 minutes and 40 seconds. The clear, simple rhythm seems to be what makes this method so successful. Here too, feel free to adapt the rigorous rules for yourself.

The Lessig method:

The Lessig method is basically a speed slideshow. This interesting presentation technique uses a large number of slides with a fast transition between slides. It allows 15 seconds (or even less) per slide, which is about four slides per minute. Due to the fast changes, the audience has little chance to drift off and is drawn into the presentation. Of course, the spoken part of the presentation needs to be perfectly synchronized with the slides. This requires practice and can make the method pretty challenging for the presenter, especially beginners.

 The Takahashi method:

The Takahashi method follows a similar principle as the Lessig method. Again, the slides only appear for a few seconds at a time. The special feature: all slides contain only one or a few words in a large font. They’re meant to underscore what the presenter is saying. Like the Lessing method, the audience’s attention is key. This method provides the presenter with key points which can make presentation tools, such as index cards unnecessary. Of course, this method is not recommended for presentations that require images, graphics or other similar visual material.

As you can see, there are many different approaches and ideas. Which method is the right one for you? The answer is up to you. It’s your presentation after all. If one of these methods and its defined guidelines works well for you, use it! Otherwise, pick and choose what you like from it and adapt it to your presentation.

Other useful PowerPoint tips:

• Your preparation should never start with your slide presentation – this should be one of the final steps. Many presenters take the opposite approach and design their presentation around their slides. This creates a false focus – the slides aren’t the focus, the presentation is. Prepare your content first and then decide how to present it in a meaningful way.

• When timing your presentation, remember to leave some room for questions, discussion or other delays. 80% of your time should be given to your actual presentation. If you take longer than planned and exceed your time, you’ll notice your audience quickly becoming restless and disinterested. If you finish a bit earlier, that’s ok. Never try to stretch the presentation unnecessarily by adding something or jumping back to a point in the presentation. Allow time to focus on your audience’s questions and comments.

• Expect the unexpected and be flexible. You may find that your audience is already pretty familiar with some of your content. If this happens, keep the presentation moving and focus more on other points. You may also need more time for questions or clarifications. This is normal during a presentation. Don’t let it throw you off balance.

• Take time to check whether all the technical equipment is working and familiarize yourself with the settings and operations. This is especially true if you work with embedded video or audio.

• Don’t give the slide presentation too much importance! Research shows that 90% of the impression a presenter makes depends on the way he or she speaks, particularly their voice and body language. It might be worthwhile to spend more preparation time on your delivery than on text and slides.

• Slide presentations are now so common in meetings that speakers feel obligated to use them. They really do offer wonderful possibilities and can be an asset to both the speaker and the audience. But this is not always the case. Not every topic needs audio-visual support via a slide presentation. And not every speech benefits from it either. Unless you’ve been explicitly told to use one, don’t feel you need to use a slide presentation if you don’t think it works for your topic.

A final word of advice:  

The biggest stumbling block in presentations is usually not the slide presentation itself, but the uncertainty of the presenter. Your listeners have probably given presentations themselves and are familiar with the challenges. They’ll most likely be forgiving of a few slides too many or too few. Stay poised and be yourself. A perfect but lifeless presentation often makes less of an impact than one with personality and a few rough edges.