Size and weight are big decision factors when you are trying to find the ideal camera for your needs.
In this section, we are going to illustrate the Panasonic ZS40 and Panasonic ZS30 side-by-side from the front, back and top in their relative dimensions. Panasonic ZS40 has external dimensions of 111 x 64 x 34 mm (4.37 x 2.52 x 1.34″) and weighs 240 g (0.53 lb / 8.47 oz) (including batteries). Panasonic ZS30 has external dimensions of 105 x 59 x 28 mm (4.13 x 2.32 x 1.1″) and weighs 198 g (0.44 lb / 6.98 oz) (including batteries).
Below you can see the front-view size comparison of the Panasonic ZS40 and the Panasonic ZS30. Panasonic ZS30 is clearly the smaller of the two cameras. Its body is 6mm narrower, 5mm shorter and 6mm thinner than Panasonic ZS40.
Here is the back view size comparison of the Panasonic ZS40 and Panasonic ZS30.
Now lets look at the top view comparison of Panasonic ZS40 and Panasonic ZS30.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Panasonic ZS30 is significantly lighter (42g ) than the Panasonic ZS40 which may become a big advantage especially on long walking trips.
Weather Sealing
Unfortunately neither the Panasonic Lumix DMC-ZS40 (Lumix DMC-TZ60) nor Panasonic Lumix DMC-ZS30 (Lumix DMC-TZ40) provides any type of weather sealing in their bodies, so you have to give extra care especially when you are shooting outdoors. If weather sealing is a must-have feature for you, check these sections: Top Compact Cameras with Weather Sealing
LCD Screen Size and Features
Panasonic ZS40 and Panasonic ZS30's LCD screens have the same diagonal size of 3.00 inches.
Unfortunately, both cameras has fixed screens so they don't tilt or flip in directions.