Boot Space Explained: VDA vs SAE, Seats-Up vs Seats-Down & Real-World Usability
Ever looked at boot space numbers and thought “Why does the US version have double the volume?” Boot space should be simple — but between VDA, SAE, litres, cubic feet, seats-up, seats-down and “to roof” vs “to parcel shelf”, most people end up more confused than informed.
We’ve written this guide to fix that. In plain English, here’s what VDA and SAE actually measure, why the numbers differ, how seats-up vs seats-down changes things, and what really matters when choosing a practical car.
We’ll use the Toyota RAV4 (ICE 2021) and Honda CR-V (ICE 2022) as real examples because both publish VDA and SAE figures, perfect to show the difference.
By the end, you’ll understand cargo space better than most salespeople.
VDA vs SAE/EPA
The main reason boot space is confusing is because car brands use two different standards. Here’s the difference between them:
VDA method (Europe & Global measurement)
VDA uses rigid 1-litre blocks stacked to fill the boot up to the parcel shelf / top of the back seats. It doesn’t cram blocks into every tiny corner, so it measures usable space.
Seats-down VDA measures to the window line.
SAE / EPA method (USA & North America measurement)
SAE fills the boot with soft bags that squeeze into every gap and measure volume up to the roof — essentially filling the boot to its maximum physical capacity.
It captures space you’d never actually use — so numbers are always larger.
This is why SAE numbers can look 30–60% bigger, and why an SUV can jump from “600 L” to “1,100 L” without the boot changing at all — just the method.
TLDR:
- VDA = usable space
- SAE = total theoretical space
Seats-Up vs Seats-Down — and why the difference matters
Seats-up is the boot measurement, with the back seats in their upright position. It tells you how much the car can hold while carrying backseat passengers.
Seats-down is the measurement of the boot + the space up to the back of the front seats, with the rear seats folded down. It tells you the maximum load for IKEA runs, camping trips, luggage, bikes etc.
But the method you use massively changes the result as VDA measures to the bottom of the windows, and SAE/EPA measures right up to the roof.
Real examples: RAV4 vs CR-V (VDA vs SAE)
Let’s take two popular SUVs that publish both systems:
Seats up
Toyota RAV4
580 L VDA (20.5 cu ft) → 1,065 L SAE (37.6 cu ft)
The capacity almost doubles from one measurement method to the other.
Honda CR-V
587 L VDA (20.7 cu ft) → 1,113 L SAE (39.3 cu ft)
Again, SAE inflates the figure by counting every last bit of upper cargo space, while VDA only measures to the parcel shelf.
Seats Down
The same pattern continues:
Toyota RAV4
1,690 L VDA (59.7 cu ft) → 1,977 L SAE (69.8 cu ft)
A difference of 287 L (10.1 cu ft).
Honda CR-V
1,634 L VDA (57.7 cu ft) → 2,166 L SAE (76.5 cu ft)
A difference of 532 L (18.8 cu ft) — noticeably larger than the RAV4.
This doesn’t mean the CR-V is taller overall. It means the CR-V has a more upright, boxy cargo shape with more “upper-airspace” above the seats, space that SAE counts (because it measures to the roof) but VDA doesn’t (because it measures to the parcel-shelf line).
Is either system “better”?
It depends what you want to find out.
VDA is realistic, it shows how much space you’ll have to comfortably use day-to-day.
SAE is impressive on paper, helpful for comparing US-market cars, but not useful for everyday packing.
If you’re comparing two cars sold in different regions, always check which standard is being used.
The part everyone forgets: shape matters as much as litres
Two cars can have the same boot volume but feel totally different because of:
- A tall, square opening vs a sloped one
- A low load lip vs a high one
- A long flat floor vs stepped sections
- Wheel-arch intrusions
- Underfloor storage
- Wide vs narrow tailgates
This is why Drivesize visuals matter — dimensions tell you how much, but visuals tell you how usable, comparing cars using our ‘Rear view’ mode helps with this.
Final Verdict
For everyday life, VDA gives the truest sense of real space, but SAE is useful for comparing US-market cars.
If a car looks like it has “more boot space” on paper, check if the number is inflated by SAE or measured realistically with VDA — and always look at seats-up vs seats-down separately.
Quick FAQs
Why are SAE boot space numbers so much bigger than VDA?
Because SAE measures to the roof, including tapered edges and unused airspace. VDA stops at the parcel shelf / top of the seats, giving a more practical, realistic result.
Which system does Europe use?
Mostly VDA. Some global models quote both — but VDA is the standard used across EU/UK spec sheets.
Which system does the USA use?
Almost always SAE (EPA).
Is a 1,000-litre SAE boot “bigger” than a 600-litre VDA boot?
Not necessarily. They’re measured differently, so you should only compare SAE with SAE, and VDA with VDA.
Is seats-up or seats-down more important?
Seats-up for families (daily life). Seats-down for large-item transport (holidays, IKEA, camping gear etc.).
Does boot shape matter more than litres?
Often — yes. A square, low, wide boot can beat a bigger-on-paper boot with awkward shapes or a high load lip.
