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 ZS100 and Casio EX-ZR300 side-by-side from the front, back and top in their relative dimensions. Panasonic ZS100 has external dimensions of 111 x 65 x 44 mm (4.37 x 2.56 x 1.73″) and weighs 312 g (0.69 lb / 11.01 oz) (including batteries). Casio EX-ZR300 has external dimensions of 105 x 59 x 29 mm (4.13 x 2.32 x 1.14″) and weighs 205 g (0.45 lb / 7.23 oz) (including batteries).
Below you can see the front-view size comparison of the Panasonic ZS100 and the Casio EX-ZR300. Casio EX-ZR300 is clearly the smaller of the two cameras. Its body is 6mm narrower, 6mm shorter and 15mm thinner than Panasonic ZS100.
Here is the back view size comparison of the Panasonic ZS100 and Casio EX-ZR300.
Now lets look at the top view comparison of Panasonic ZS100 and Casio EX-ZR300.
Weight is another important factor, especially when deciding on a camera that you want to carry with you all day.
Casio EX-ZR300 is significantly lighter (107g ) than the Panasonic ZS100 which may become a big advantage especially on long walking trips.
Weather Sealing
Unfortunately neither the Panasonic Lumix DMC-ZS100 (Lumix DMC-TZ100) nor Casio Exilim EX-ZR300 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 ZS100 and Casio EX-ZR300'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.