Serving size for a small dog *Updates with pictures*

It truly depends on metabolism and energy use level, every dog, irregardless of size is different.

I have a little chihuahua/dachsund mix at 6#, I keep him on the real thin side, probably just a very slight tad underweight cause he does have luxating patella issues that are almost non-existant as long as I keep him thin.

Even so, he can put away nearly a pound of food a day (he eats fresh foods with a lot of moisture); he's not super high energy, but he does have a FAST metabolism. If I fed him dog food, I'd say he could eat around 1 to 1.5 cups of food and this is a 6# dog.

Whereas my other 6# dog only requires 4-6oz of food a day; just depends.

 I feed Tootsie 1/3 of a cup, 2x daily and shes 26 lbs. Shes not a typical corgi, not high-energy at all.

 Emma (19 lbs) eats roughly 800 kcals a day. She's 5 years old, and a moderately active pet. Not super boingy, and not a sport dog or anything like that.

Ena (13 lbs) eats ...  Way less! Oops, I can't find the kcals on her kibble. I would guesstimate half as much. She's 17 months, and also moderately active. I keep both dogs lean. Ena has a luxating patella, and Emma has spinal issues, and an arthritic hip.

 As far as cups, Emma gets 2 1/2 cups, plus a small can of prescription food. Ena gets a cup of dry, a spoonful of canned, and some treats.

Casey is 13# and eats 1/2-3/4 c. a day. depending on how active he is, and if I add anything else to it. I alternate between eggs, yogurt and canned for toppers. Depending on what, and how much of what I'm adding, the kibble amount varies. He's a soild, compact dog too - I'm very pleased with his weight.

 Kujo is 4lbs and eats 1/2 cup of TOTW and whatever scraps Samantha gives her throughout the day.

 Your dog looks excellent for her age. I'd be concerned with a younger dog, for being a smidge on the skinny side, but it's hard to tell without the touch test. Terriers get hard muscle from the spine through the ribs but you can tell the difference easily by touching. And the top view doesn't show any vertebrae. That's when I get worried on a working-type dog.

Grimm is about 13# and gets 1 cup each day.  Soon we'll be cutting him back, when he gets a bit closer to a year.

The elf gets 1/4 c each day and is 10# at the moment. 

 Jules is 12# and gets just over 1/2 c per day

 Jetta is 15 lbs and eats 1/2 cup kibble per day on a medium-calorie dense dog kibble. If I fed her a high cal one she has to eat way less and still is chubby, so I don't like to give her dense food.  She is pretty inactive except for short daily walks and games of fetch.

 Poor Jetta gains weight just by looking at food tho...

 My brother has a 12 lb min pin who eats over 1 cup per day, and she is still skinny even though she doesn't exercise much. It all depends on the dog, I guess.

I don't think she looks too skinny at all -- especially if you're doing agility.  We like them thin & sporty in agility. 

So long as she has the energy to "get the job done," I think she's just fine.

Luke is 85 lbs and only gets 2 cups of Taste of the Wild per day.  I generally bump it up to 3 cups on trial weekends and throw in protein powder to give him an energy boost and to help with the added physical requirements of the day.

I have no idea what Kaiser (17 lbs) eats.  I keep food out for him 24/7 just to make sure he eats SOMETHING and he picks at it all day.  There are some days when I'm sure he must only eat about 1/2 cup, but then the next day he'll catch up and eat about 1 1/2 cups.  He maintains a trim weight all on his own, so I figure I'll continue to let him do this.

 Ok, Bean's kibble has 420 kcal/cup, so she's getting roughly 500 kcal/day.

I agree, though, that  Sandy looks really good. She looks lean, and heavily muscled.

 I can feel her ribs with a thin layer of muscle but when she lays down I can feel and see a portion of her spine. She's always been like this but not when she's standing.  I guess I'll keep her at 1/2 cup and see what she does. She still has the energy to keep up with me on the field (And bark when I mess up lol) so there's no worry there.