PackIt is the answer. Eight hours is a realistic number.

For an integrated refreezable ice pack, PackIt’s freezable lunch bags are the ones to get, and you can expect about 8 hours of genuinely cold food.

The whole point of PackIt is that the ice pack isn’t a separate slab you wedge in next to your sandwich. It’s sealed into the lining of the bag itself, so basically every wall is cold. That gives you way more cooling surface area than a single loose pack, which is why these bags outperform most ordinary lunchboxes with add-on ice.

The manufacturer says “up to 10 hours.” That’s best-case: frozen overnight, packed with cold food, left closed in an air-conditioned room. In real life — car, outdoor work site, frequent opening — plan for 7–8 hours. That still covers a normal workday.

Two tips: freeze it flat and give it a full night in the freezer, and don’t put warm leftovers in there. Cold food in, cold food out. If you genuinely need all-day cold for 12+ hours, you want a real cooler with heavy separate ice packs, not an integrated lunch bag.

PackIt makes a few sizes, from small snack bags to bigger totes, and they’re all fine. Just pick the one that fits your lunch, not the one with the most features.