We want to buy a deep freezer. We want to put it in a storage area between our dining room and garage. Here's the issue: The outlet in the storage area is on the same circuit as the 1/2 h.p. garage door opener (max 5 amp according to plate) and the dining room lighting fixture and 2 outlets- which only ever get used to charge cell phones. They are on a 120 V/20 amp circuit breaker. The dining room pendant light is connected to a dimmer switch, and are currently using two 60 watt light bulbs. Would a 7.0 cu chest freezer overload this circuit? (We looked into running a dedicated circuit but it cost too much.)
I checked the freezer I was interested in and it said 115V/1.7 Amps. Sounded really low to me, but heck, what do I know. It was a G.E. 7.0 cu freezer.

The one piece of info that is really needed to answer this question accurately is not given: the wattage or volt-amp rating of the freezer.

That being the case, let’s do this backwards.

The circuit is rated at 20 Amps.
20Amps = 2,400 Watts (volt-amps) at 120 volts
80% of the circuit is then 1,920 Watts (just for safety, let's use this number)
If the stated maximum current draw for the opener is 5 Amps, as stated on the name plate, that equals 600 Watts. You have 1,320 Watts left over.
Say your two dining room light bulbs are burning 24-7, that uses 150 Watts (120 x 1.25 for being a "continuous load" - being on for more than 3 hours)
You have 1,170 Watts "left" on that circuit.
The cell phone chargers are probably less than 2 amps, combined. Let's call them 250 Watts, just to "pad" that a little.
You still have 920 Watts "left" on this circuit.
If the freezer is rated at 8 Amps or less you are very safe. I would even go as far as saying that at 10 Amps I would trust the circuit; the chances of all of these loads being applied to the circuit at one time are between slim and none.

The opener is only running when raising or lowering the overhead door.

The Dining room lights are not always on.

The freezer better not run continuously or it has a bad thermostat.

You have all non-concurrent loads; if it is 8 or 9 Amps; plug it in, then, fill it up.

(I did this in my head as I was sitting here, so double check the math.)