It can be hard to tell if a single tube of paint is “worth” its price. Even more so if tubes of paint don’t seem to come in the same sizes!
Here’s a quick comparison using gouache paints as an example:
This 5 color set of M. Graham Gouache paints on Amazon is $25.99 – say about $26, meaning it’s about $5.20 a tube. Each tube of paint is a half ounce.
Now compare with another brand:
Holbein 5 color mixing set – with 15 ml tubes, for $20.90. So about $4.18 a tube.
But wait – we’re comparing a half ounce to 15 mililiters. Luckily, that’s almost the same weight, if you do a conversion. A half ounce is about 14.7 ml, so they’re more or less the same amounts of paint.
Holbein’s paint set is cheaper all around.
But let’s also compare sets to single tubes. That same M. Graham Gouache paint tube of a half ounce of Cobalt Blue paint? If you buy it alone on Amazon, that’s now $6.65 – so in this case you’re paying $1.45 more to buy a single tube of the color. If you look at the single tube in the Holbein set, it’s about $6.89. Buying open-stock (or single tubes, in this case) is usually only cheaper in Art supply stores and when you’re buying more than a few colors, not on places like Amazon.
In any case, both of these sets are cheaper than buying the same single tubes, so if you wanted all five primary mixing colors of a gouache, try a set.
And in case you were wondering, it’s fair to check pigments against each other. The cost of a pigment can determine how expensive a paint ends up. These two blues are actually different pigments – Holbein is PB15 (Pthalo Blue), and M. Graham’s Cobalt is PB28 – which is Cobalt pigment. You can compare the Reds/Magentas in these sets as well: Holbein’s primary Magenta is actually Quinacridone Magenta (PR122), whereas M. Graham’s red is Naphthol Red (PR112). The former is a magenta (pinky-blue cool red), and the latter is a more scarlet (warm) red. Both are good, and they’re both good single pigment mixing paint colors. The difference in price here might just be pricier pigments included in the M. Graham set. And knowing that, you can choose whatever’s best – or cheapest.