Crowds in Amsterdam in late August?

Rjks and VG are two of the most popular art museums in the world, so they will indeed be crowded. Best to visit right as it opens or a couple hours before closing to avoid crowds. The excellent Hermitage Museum is more manageable midday. Also be aware that Sept 14-19 each year Amsterdam hosts the International Broadcasters convention. It's one of the largest conventions in the world and hotel rates will be sky high.

Also be aware that Sept 14-19 each year Amsterdam hosts the
International Broadcasters convention. It's one of the largest
conventions in the world and hotel rates will be sky high.

Very good advice from Michael. We ended up switching the order of our Paris-Amsterdam weeks a number of years ago precisely because of this issue. Hotel rates were just insane.

The museums/tourist areas were really busy the third week of Sept.

Be sure that you order your timed entry tickets in advance and print them at home. The lines to buy tickets will be hours long and they could sell out by early afternoon. (There is some capacity control.)
I am embarrassed to say that I did not do this for my recent trip in late October (I did have reasons ... but still ...)
and I waited in line for over 1 1/2 hours for Van Gogh, although only half an hour for The Rijksmuseum.
Be smart!

There are so many rooms in the Rijksmuseum that you can get away from crowds except in the Dutch Masters rooms. Crowds there are inevitable, and you will see tours and cruise groups, so go there as soon after opening as you can. Buy your tickets online or from your hotel so you'll have one less line in which to stand.
Also, keep your ticket in your pocket or close at hand as you may have to show it as you go through the restrooms and the wings.
We left the museum, had a little lunch nearby, re-entered and finished- about 6 hours. The museum cafe had a long wait. This was my third visit to the Rijksmuseum and it was phenomenal.
I suppose some people could go to both the Rijksmuseum and the Van Gogh in one day, but it would be art overdose for me.

I like Amsterdam and have been there several times- but the crowds around the Dam and Centraal Station are a bit much; I hope you are staying in a lovely area. Five to seven days is not too long if you like museums and walking the canals and relaxing.
I second the Hermitage Museum recommendation, if you like the current exhibition- have only been mildly disappointed in one of them. You might enjoy Rembrandt's home- only an hour needed for it.

Thanks for the responses!

Michael, we'll avoid those September dates for staying in Amsterdam. We may be in the Netherlands then, but will probably stay in some town like Delft or Utrecht. Not sure just yet but the plan is to fly back into AMS and stay for a few more days in the Netherlands before winding up our trip.

Melissa, it sounds like the Rijksmuseum situation is much like the Louve in that the very popular art is most crowded. We'll definitely get there at the opening. You've motivated me to get accommodations in the quieter (perhaps pricier) neighborhoods. We may be in Amsterdam about 6 nights or so. Plenty to do there and on day trips out of Amsterdam according to the RS book.

... but will probably stay in some town like Delft or Utrecht
Excellent suggestion. There is no need whatsoever to stay in crowded and overpriced Amsterdam. Haarlem is a beautiful city and only 15 minutes by very regular train from Amsterdam. Leiden is another historical city and only 35 minutes from Amsterdam with 4 direct trains per hour. Utrecht the same.

Les - We did both the Rijks & Van Gogh museums this past June. I would highly recommend purchasing your tickets for the Van Gogh museum in advance and as early in the day as possible.