Here’s the short answer: plan on about 150 words for every minute of video. A 10-minute YouTube video needs a script of roughly 1,500 words, and a 60-second Short needs about 150. That number is a starting point, though, and I’ve written enough scripts to know it bends. The format, how dense the information is and how your narrator talks can push it up or down by a few hundred words.
I wanted a number I could defend, so I went looking for real measurements of how fast people speak and read aloud. Below is the table I use, where the number comes from, and why our own 10-minute documentary script came out longer than the table says it should.
Script length by video length
The first column assumes a calm, clear narrator at about 150 words per minute. The second assumes a livelier read at about 170, which is closer to how a lot of storytelling channels sound.
| Video length | Calm pace (150 wpm) | Lively pace (170 wpm) |
|---|---|---|
| 1 minute | 150 words | 170 words |
| 3 minutes | 450 words | 510 words |
| 5 minutes | 750 words | 850 words |
| 8 minutes | 1,200 words | 1,360 words |
| 10 minutes | 1,500 words | 1,700 words |
| 15 minutes | 2,250 words | 2,550 words |
| 20 minutes | 3,000 words | 3,400 words |
These counts are for spoken words only. Scene notes, on-screen text and source links don’t count, because they never get read out loud.
Where 150 words a minute comes from
The most practical figure I found comes from people who narrate for a living. ACX, Audible’s platform for audiobook producers, tells authors in its guide to audiobook length that “on average, most performers narrate about 9,300 words per hour.” Divide that by 60 and you get about 155 words a minute.
Research lands in the same place. In 2019 the psychologist Marc Brysbaert at Ghent University pulled together decades of studies on reading speed in a review published in the Journal of Memory and Language. He reports that “audiobooks are spoken at a rate of 140–180 wpm.” The same review found that people reading aloud in experiments average 183 words a minute, but he calls that pace “an unrealistic rate for day-to-day use.” A study session is short. A 15-minute voiceover isn’t, and your narrator needs room to breathe.
So 150 is a calm, sustainable middle. It’s a good default when you don’t know yet who will read the script.
Our 10-minute script ran faster than that
Here’s where real work disagrees with the neat number. The documentary script we wrote about Brunei’s royal family was planned to run just over ten minutes. When I counted only the words the narrator says, leaving out headings, cues and source notes, it came to about 1,750 words. That’s close to 175 words a minute, well above the calm column.
It worked because the read was meant to move. The script mixes quick lines that carry the story with slower, quieter moments marked by pause cues, and the faster stretches pull the average up. I walk through that structure in our guide to writing a YouTube documentary script.
There’s a limit to how far you can push, and it depends on how much each sentence asks of the listener. A study by Emma Rodero at Pompeu Fabra University, published in Media Psychology in 2016, played radio news to 200 students at five speeds. People remembered the most at about 170 words a minute when the news was packed with facts, and at about 190 when it was lighter. Her rule is easy to remember: “The higher the speed, the lower the information density should be and vice versa.” The study used Spanish speakers, so I treat the exact numbers as a guide, but the idea matches what I hear in edits. A dense explainer needs a slower read than a story.
The kind of video changes the pace
Different formats settle into different speeds. A 2024 study in the journal Ibérica by researchers at the University of Montenegro compared 21 science podcasts with 21 university lectures. The podcasts averaged about 168 words a minute. The lectures averaged about 153. Both explain science, but one is trying to keep a listener who can leave at any moment.
For YouTube, that suggests a few rough rules. Tutorials, where viewers copy each step, sit near the calm column or below it. Explainers with lots of numbers sit near 150 to 160. Stories, commentary and documentaries can run in the 160s and 170s. If your narrator is someone else, ask for a one-minute test read and do the count yourself. That’s your real number, and it beats any table, including mine.
Many viewers will speed you up anyway
This part surprised me. In a UCLA study in Applied Cognitive Psychology, students watched recorded lectures at normal speed, 1.5 times, twice and two and a half times as fast. The researchers found “minimal costs” up to double speed, and scores only dropped beyond that. In the group that watched at normal speed, 60% said they usually watch lectures at 1.5 times.
That doesn’t mean you should rush. It means padding is the bigger risk. If a viewer is already playing your video faster, a slow, wordy script gives them a reason to keep clicking ahead. Tight writing at a natural pace respects both kinds of viewer.
Let the video’s job set the length
Word counts follow from video length, so the real decision comes first: how long should the video be? YouTube doesn’t publish an ideal length, but its own rules shape the choice. Shorts can now run up to three minutes, so a Short script can go up to about 450 words, though most land well under that. Mid-roll ads are only available on monetized videos that are 8 minutes or longer, which is why so many channels aim for at least eight.
Stretching a five-minute idea to eight minutes for an extra ad break usually backfires, though. YouTube’s recommendations care about more than clicks. In a post on how the system works, YouTube’s Cristos Goodrow explains that “clicking on a video doesn’t mean you actually watched it,” which is why watch time was added in 2012, and that YouTube also measures “valued watchtime” through surveys that ask viewers to rate what they watched. A padded script hurts both. And its audience retention report lets you compare your video with “all YouTube videos of similar length,” so a long video is judged against other long videos.
How to hit your target
- Decide the video’s length from its job: one idea for a Short, a full story or tutorial for 8 to 15 minutes.
- Record your narrator reading one minute of any script and count the words. Use that as your pace.
- Multiply your pace by the target minutes to get a word budget.
- Write the draft, then count only the spoken words.
- Read it aloud with a timer. Cut lines you stumble over before cutting ideas.
- If you’re far over budget, remove a section instead of trimming words from every sentence.
If you’d like to see what a finished 10-minute script looks like, with every cue and source in place, you can read the opening of our Brunei script and request the rest. And if you want one written for your channel, scripts are part of our writing work.
