This week on the channel +22M views this week

Veritasium puts a positive test through a probability check

Two new uploads pair a street-side statistics puzzle with a professionally controlled gunpowder demonstration.

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Veritasium Story of November 15, 2026Trari Newsroom

Why this story? The channel's weekly summary: what went up this week, what is drawing views now, and where the channel stands among similar channels.

Why you can't trust a test that's 99% accurate

What did you think?

A pedestrian's "very weird math" gets surprisingly close to the answer in Veritasium's most-watched new upload. Other guesses range from near certainty to an either-or coin toss, but the puzzle needs something intuition can easily overlook: how rare the disease is to begin with.

In "Why you can't trust a test that's 99% accurate", the host asks what a positive result means when a disease affects one person in a thousand. An animated dot diagram supplies the missing perspective. Even a small false-positive rate produces many more positive results among the much larger group without the disease. In this example, the chance of actually having it after testing positive is only about 9%.

The Short has reached roughly 1.5 million views. Viewers are discussing both the interviewee whose mental arithmetic came close and the wording of "accuracy", with several asking for a clearer distinction between false positives, false negatives and the probability that a positive result is correct.

The other new upload, "Making Gunpowder From Scratch", takes the week from statistical surprises to chemistry. Its description specifies that professionals performed the demonstration in a controlled environment.

Beyond those two uploads, the helium documentary remains the channel's busiest video right now. Presented by Derek Muller and Casper Mebius, it connects the pursuit of absolute zero with superconductivity and superfluidity. Henry van Dyck's fiber-optics film is also continuing to draw viewers.

Veritasium's subscriber total held steady, while its daily views are well below their usual level. That softer daily picture coexists with the largest weekly view gain among these science peers; AsapSCIENCE, meanwhile, is enjoying daily viewing well above its own norm.

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Where next?

Also in Science and experimentsVideo taking off 27x its usual first dayScott Manley examines Super Heavy's tower abort and green flareHis fast-starting Short separates the reported reason for abandoning the tower catch from what happened just above the water.Channel: Scott Manley · Story of November 15, 2026

A different discovery todayVideo taking off 5x its usual first dayCaptain Steeeve traces the FAA ground stop to a system called ERAMFilmed at Detroit Metro Airport, his explainer runs from a failed network update to what pilots do when the radio goes quiet.Channel: Captain Steeeve · Story of November 15, 2026

What viewers say

“My very weird math” turns out to be close enough😂😂😂
@talosthebot3168See it on YouTube
That's why you look at the confusion matrix. True positive, True negative, False positive, False negative :)
@nocturn9xSee it on YouTube
I think it depends on what “99% accuracy” means.
@MichaelWillemsSee it on YouTube

2 more comments

I would've assumed the amount of people is irrelevant for a single test.
@theapocasmithSee it on YouTube
I feel like the meaning of the provided numbers wasn't sufficiently well defined to reliably solve this quiz correct.
@maxpower586See it on YouTube

Public comments from the video's page on YouTube