The verdict
The PETLIBRO Granary 2 Smart Feeder takes #1 as the only feeder that weighs the bowl to the gram, so what your pet ate is measured, not estimated. The AmRank Top Pick is the #2 PETLIBRO Granary WiFi — the proven model of the same line, $40 cheaper, with a D-cell backup that runs for days through an outage instead of hours.
Questions, answered
Will an automatic feeder keep feeding my cat during a power outage?
Only if it has battery backup, and the models here differ enormously. Picture the real scene: a storm kills power on the Friday night of your weekend away. The two PetSafe conveyors and the PETLIBRO Granary WiFi run for days on D-cell batteries. The Granary 2's built-in rechargeable cell covers about 24 hours. The PETKIT Solo's five AAA batteries are a short bridge, and the Whisker Feeder-Robot's backup battery is a $40 extra — as sold, an outage stops it. The Cat Mate C500 runs on AA batteries full-time, so an outage is a non-event. Note that Wi-Fi dropping is a different failure: every ranked feeder stores its schedule on the device and keeps dispensing without a connection.
How accurate are the portions, really?
Rotor and conveyor feeders dose by volume, not weight, so the same setting delivers slightly different grams when you change kibble size or density — expect drift, and weigh a few dispenses when you switch foods. Step size matters more than marketing: the WOPET Patrol doses in 5 g steps, most PETLIBRO models in roughly 10 g (1/12 cup) steps, and the Petory F01 in 10 g steps only, with a finer 5 g rotor sold separately. The Granary 2 is the exception that proves the rule — it weighs the bowl to within a gram. The Cat Mate C500 is exact for a different reason: you portion each compartment by hand before you leave.
What size kibble can these feeders handle?
Most ranked feeders accept dry kibble from 2 to 15 mm. The PETKIT Fresh Element Solo caps at 12 mm, and freeze-dried pieces at 9 mm. The two PetSafe conveyor feeders are the most forgiving, handling dry and semi-moist pieces up to 3/4 inch across. Oversized and irregular pieces are the classic jam: PETLIBRO warns against cubes larger than 9 mm and crescent shapes even inside its 15 mm limit. Measure your kibble with a ruler before ordering — a feeder matched to the wrong food fails in the first week, not the first year.
Can one feeder serve two cats fairly?
A single shared bowl cannot. The bold cat eats, the shy cat watches, and the feeder faithfully logs one 'successful' meal. Dual-tray variants (in the pool below) split one dispense into two bowls, which helps only if both cats eat at the same speed. True per-cat control needs selective hardware: the PETLIBRO One RFID unlocks its bowl lid only for the cat wearing its collar tag — one tag per feeder, so a two-diet household needs two feeders. Microchip access bowls (SureFeed, in the pool) do the same job for a bowl you fill yourself, but they do not dispense or schedule anything.
How long can I actually leave my cat with an automatic feeder?
The food math is generous — a 5L hopper holds roughly 30 days of food for a typical 5 kg cat eating about 80 g a day, on PETLIBRO's own figures — but food is not the binding constraint. Water, litter and a welfare check are: plan on a feeder covering a long weekend cleanly, with a person checking in every couple of days on longer trips. Also match the feeder to the absence: the Cat Mate C500 serves five meals and then it is done, which is perfect for two days of wet food and useless for a week, while the hopper feeders above it were built for exactly that week.
Prices checked October 16, 2026, on US sellers' pages for the exact model named, base single-pet configuration, rounded to whole dollars. Unless a card says otherwise, the price is the manufacturer's own US store price: PETLIBRO, PETKIT, Whisker (litter-robot.com) and Closer Pets all sell direct at the prices shown, and the PetSafe Smart Feed price is petsafe.com's. The Simply Feed's $96 was listed by both petsafe.com and PetSmart. The Petory F01 is sold through Amazon US; its price is the Amazon listing for the dual-power variant (ASIN B09L15DBFF) at check time. Backup batteries, desiccant refills, spare bowls and app subscriptions are extra unless the maker includes them in the box. Prices are typical US street prices observed during research and change often — check the retailer for the current price. AmRank may earn a commission from links on this page; commissions never change a score. See the affiliate disclosure and methodology.
