PackFitter
Packing Calculator & Fit Tool
Plan. Pack. Fly.
Last updated: April 2026
A 5-day trip usually means 4–5 core tops, 1–2 bottoms, one mid layer, and a small toiletry kit — which takes up roughly 25–35 liters depending on climate and packing style. Most travelers can fit this in a carry-on bag if they pack efficiently and skip bulky extras.
Check if your packing setup fits your bag →Volume depends primarily on clothing quantity, climate layers, and whether you're packing a laptop or extra shoes. Upper-body packing shifts noticeably between climates — warm trips lean on lightweight tops, while colder trips swap in heavier mid layers. Most standard packers land in the 25–35L range for 5 days without laundry access.
Warmth comes from layering, not from packing more shirts. You wear the bulkiest layer — a heavy jacket at the airport takes up zero bag space. Inside the bag, one compressible mid layer (fleece, lightweight down, or insulated mid) handles most cold-weather needs. Two thin layers outperform one heavy layer and compress significantly better.
For a 5-day trip in cold weather, wearing your heaviest layer and packing one compressible mid is the most space-efficient approach. Your core top count stays the same — the climate difference shows up in layers, not shirts.
Prefilled for a 5-day trip — adjust to match your setup.
Based on real clothing volumes and packing behavior
For most travelers, 5 days is where a 30–40L carry-on offers the best balance of space and portability. Staying at 30L keeps you nimble and personal-item-compatible on some airlines. Sizing up to 35–40L gives you room for extra shoes, a laptop, or heavier layers without compression stress — and still fits carry-on limits on every major airline.
Airline fit for 5 day trip bags
Will a 35L backpack actually fit on Delta? →
Will a 35L backpack actually fit on United? →
Will a 40L backpack actually fit on American? →
Other trip lengths
What to pack for a 3-day trip →
What to pack for a 7-day trip →
What to pack for a 10-day trip →
Browse all guides
Volume estimates are based on real clothing measurements, standard packing behavior, and a 15% gap factor for dead space inside the bag. Results vary by bag design, clothing thickness, and how tightly you pack.
The calculator uses the same engine as the airline-specific pages — it accounts for climate, packing style, laundry access, shoes, laptop, and bulky layers. It uses four packing profiles (ultralight, light, standard, and heavy) to reflect different real-world packing styles. Airline carry-on limits are based on published dimensions.
This is a general guide. Final bag acceptance depends on airline discretion and your bag's packed external dimensions.
This content reflects real-world packing scenarios and typical airline policies. Airline enforcement may vary based on aircraft, route, and boarding conditions.