An online course lesson should be as short as it can be while still teaching one idea completely. For most video lessons, I’d rather see six minutes than sixteen, and the research on video engagement backs that up.

That doesn’t mean every lesson needs a stopwatch. It means the length of a lesson should come from what the lesson is trying to do, not from how much you have to say about the topic. After 15+ years as an instructional designer, the most common lesson problem I see isn’t “too short.” It’s one lesson trying to carry four ideas at once.

What does the research say about video lesson length?

The best-known study on this found that people stop watching long videos well before the end. Researchers looked at 6.9 million video watching sessions across four edX courses and found that median engagement time was at most 6 minutes, regardless of how long the video was. Their recommendation was to break videos into short chunks, ideally less than 6 minutes (Guo, Kim, and Rubin, L@S 2014).

First, a longer video didn’t buy more watching time. It mostly bought more video that nobody saw. Second, this was a study of large free courses, and your paid course with your own audience isn’t the same situation. I treat that 6-minute number as a strong hint, not a hard rule. But the direction is clear, and it matches what I see in the courses we build.

So how long should my lessons be?

Here’s how I decide: one idea per lesson, and the lesson ends when that idea is taught and the student knows what to do with it. In practice that usually lands somewhere in the 5 to 15 minute range for video, with a lot of lessons on the shorter end.

This is roughly how I think about it by lesson type:

Lesson type	What it’s for	How long I’d usually aim for
Welcome or orientation	Show students how the course works and what they’ll get	A few minutes. Get them to the first real lesson fast.
Concept lesson	Teach one idea or one step of your framework	Short. Aim for under 10 minutes when you can.
Walkthrough or demo	Show the student how you do the thing, step by step	Can run longer, because they’re following along. Break it at natural pauses.
Worksheet or action lesson	Have the student apply what they just learned	The video is short. The doing takes as long as it takes.
Live call replay	Q and A, coaching, or hot seats	Whatever the call was, but add timestamps or a summary so people can find what they need

The pattern is that teaching lessons should be tight, and doing lessons can stretch. A 25-minute walkthrough where the student is building something alongside you is very different from a 25-minute lecture.

Why do shorter lessons help students finish?

Shorter lessons are easier to start and they give students more finish lines. Ten minutes feels doable on a Tuesday night. An hour feels like something to save for later, and “later” is where courses go to die.

Every completed lesson is also a small win. A course with 30 short lessons feels faster than a course with 8 long ones, even when the total content is the same, because the student keeps checking things off. Buyers crave momentum, not modules.

This matters a lot for completion. Most courses see 5 to 15% completion. Katie averages 64%, and part of how she got there was making the program tighter and easier to move through each time she worked with us. I wrote about the rest of that in why most students don’t finish online courses.

How do I know if a lesson is too long?

A lesson is too long when it’s covering more than one idea, or when you can’t describe what the student should do after watching it in one sentence. Length on its own is a symptom. The cause is usually scope.

Run your lessons through these checks:

• Can you name the one thing this lesson teaches in a few words? If you need “and” twice, it’s probably two or three lessons.
• Is there a natural pause in the middle where you change topics? That’s a good place to split.
• Are you giving background that the student doesn’t need to take the next step? Cut it or move it to a resource.
• Are you telling the same story or example twice to make the point? Keep the better one.
• Would the student know what to do the moment the video ends? If not, the lesson needs a clear action step more than it needs more content.

Can a lesson be too short?

Yes, though it’s much less common. A lesson is too short when it leaves the student without enough to do anything useful.

The other version of “too short” is chopping one idea into five tiny videos just to hit a length target. That adds clicking without adding clarity. One idea, taught completely, is the goal. Sometimes that’s three minutes and sometimes it’s twelve.

Should I split a long lesson into several shorter ones?

Usually, yes, and it’s one of the fastest ways to improve a course you’ve already recorded. You don’t always need to re-record. Many long videos can be edited into shorter lessons at the natural breaks where you moved from one point to the next.

Here’s the order I’d work in:

1. Pull up your longest lessons and watch for the moments where you change topics.
2. Mark each break and give each section a clear, specific title.
3. Check whether each new piece has an action step. Add a checklist or worksheet where it doesn’t.
4. Cut any section that doesn’t move the student toward the result you promised.
5. Re-record only the transitions that don’t make sense once the video is split.

If you find yourself splitting almost every lesson, that’s a sign the bigger issue is structure. A clear framework makes lesson length much easier to manage, because each step of the framework gives you a natural boundary. If you’re working on that piece, how to simplify your framework without losing depth is a good next read.

Does lesson length depend on the price of the course?

No. A higher price raises what students expect from the result, and longer lessons don’t deliver that. I know it’s tempting to make an expensive course feel “worth it” by making it big, but students pay for the outcome. Make your course simpler, not longer.

Frequently asked questions

What is the ideal length for a course video?

For most teaching videos, shorter is better. One well-known study of edX videos found median engagement topped out at about 6 minutes no matter how long the video was. I usually aim for one idea per lesson, often under 10 minutes.

How many lessons should be in a module?

Enough to teach that stage of your framework, and no more. I’d rather see a module with a handful of tight lessons than one with a dozen that repeat each other. Let the framework decide, not a number.

Are long lessons bad for completion?

They often are, because they’re harder to start and give students fewer finish lines. Long lessons also tend to carry more than one idea, which makes it easier for students to get lost and stall.

Should course lessons be the same length?

No. Lessons should be as long as the one idea they teach. Concept lessons tend to be short, and demos or walkthroughs can run longer. Consistency in structure matters more than consistency in length.

Get your lessons planned and recorded

If you know what you want to teach and you’re ready to get it organized into lessons that people actually finish, the Get It Done Course Kit can help you get there. It’s $97, and it’s designed to help you move from a pile of ideas to a course you can sit down and record. Just show up with what you know.

Ariel Schiffer is the founder of Dreampro and an instructional designer with 15+ years of experience designing learning programs for Fortune 50 companies and nonprofits. She holds an M.A. in Industrial-Organizational Psychology.