Start with the bag, not the list
A hard limit — one checked bag per two travellers, one cabin bag per person — forces every packing decision after it. Soft-sided bags flex into overhead lockers better than hard-shell cases, and a cabin bag with a laptop-style compartment doubles as an under-seat bag for a change of baby clothes. Decide the bag first and the list writes itself around what actually fits.
Clothes: pack for the wash, not the week
Five days of outfits is enough for any trip longer than five days, because hotel laundry, a launderette, or a sink and a travel-size detergent sheet covers the rest. Pack one layer warmer and one layer cooler than the forecast suggests — weather apps are unreliable more than three days out, and children run warmer or colder than adults expect.
The one bag that never checks
Documents, medication, one full change of clothes per child, and any irreplaceable item travel in the cabin bag, never in checked luggage. A printed copy of passports, insurance details and any prescription, kept separately from the originals, turns a lost-bag problem into an hour’s inconvenience instead of a day’s. This is the bag packed last and watched most closely.
What changes by climate — and what doesn’t
A trip built around Copenhagen‘s cooler, changeable weather needs real layers and a waterproof shell; Cape Town asks for sun protection and a lighter jacket for cool evenings even in summer. Tokyo shifts dramatically by season, from cherry-blossom mild to summer humidity that makes quick-dry fabric worth the extra packing space, and Sydney‘s seasons run opposite the northern hemisphere’s, so a “summer” trip in January needs the same kit as a European July. What never changes: sun hats, a basic first-aid kit, and one comfort item per child that stays in the cabin bag no matter what.
What to leave at home
Skip the “just in case” third pair of shoes, full-size toiletries, and any toy that needs charging and isn’t already a genuine favourite. Nearly everything forgotten can be bought on arrival in any of the destinations on this site; very little that’s packed “just in case” ever actually gets used.