1Rank 01 of 10 · Air Fryers
Ninja Double Stack XL SL400EU
Two stacked 4.75-litre drawers on a 28 cm-wide footprint, and the only model here with an independent lab figure for how many frozen fries it really takes.
8.2BPR score
- €130Price
- 9.5 L (2 × 4.75 L), 2,470 W — OCU measured 2,266 g of frozen fries, the highest in this rankingBasket capacity (litres) with rated power (W) — and OCU's measured frozen-fries load where available
- 1 of 10in Air Fryers
- 8.2BPR score 0–10
Review
What this product is
Written after the analysis, from the same sources the score is built on: the manufacturer's documentation, available studies and verified owner feedback.
The Double Stack solves the usual dual-drawer problem — width — by stacking the two 4.75-litre drawers vertically. The geizhals listing gives 280 × 385 × 470 mm (W × H × D), so it occupies roughly the counter width of a single-basket fryer while offering 9.5 litres in total.
What lifts it to the top is evidence. OCU's comparator measured 2,266 g of frozen fries for the SL400EU, more than any other model in this ranking and more than twice the 1,000 g it measured for Philips' 4.2-litre NA221. Stated temperature range is 40–240 °C, with six programmes plus Match and Sync functions for finishing both drawers together. On geizhals the model averages 4.7/5 from 326 ratings.
The trade-offs: 2,470 W is a high peak draw, and Ninja publishes no energy-per-batch figure, no noise level and no coating chemistry beyond 'non-stick'. Ninja's own German and Spanish shops refused automated access during our research, so specifications come from geizhals rather than the manufacturer. At about €130 street price it is good value for a family-sized machine.
Best for: families of three to five who cook a main and a side at once and have a narrow counter.
Technical data
Specification
Figures from the manufacturer's documentation, verified against available outside sources. Values we could not confirm are marked as declared.
- Total capacity
- 9.5 L
- Drawers
- 2 × 4.75 L, stacked
- Rated power
- 2,470 W
- Temperature range
- 40–240 °C
- Programmes
- 6
- Dimensions (W × H × D)
- 280 × 385 × 470 mm
- OCU frozen-fries capacity
- 2,266 g
- Dishwasher-safe parts
- Yes
- Noise
- Not published
- Street price (geizhals, Oct 2026)
- €130.00
Component scores
Where the score
comes from.
Four components, equal weight, each on a 0–10 scale and each resting on a named source. The overall score is their mean — the full procedure is in the methodology.
What we liked
- OCU lab measured 2,266 g of frozen fries — highest here
- 9.5 L in two 4.75 L drawers on a 280 mm-wide footprint
- 40–240 °C range and 6 programmes
- Match and Sync for finishing both drawers together
- 4.7/5 from 326 ratings on geizhals
Worth knowing
- 2,470 W peak draw; no energy-per-batch figure
- No noise figure published
- Coating chemistry not disclosed
- Specifications not verifiable on Ninja's own site (blocked)
Comparison
How it compares
within the category
All values come from the same analysis and are comparable only within the category Air Fryers.
| Product | Score | Basket capacity (litres) with rated power (W) — and OCU's measured frozen-fries load where available | Price |
|---|---|---|---|
| Double Stack XL SL400EUThis product · top score | 8.2 | 9.5 L (2 × 4.75 L), 2,470 W — OCU measured 2,266 g of frozen fries, the highest in this ranking | €130 |
| Dual Basket 8.5 L CAF-R901Runner-up | 8.1 | 8.5 L (2 × 4.25 L), 1,750 W — published by Cosori; not in OCU's comparator | €117 |
| Category average10 products analysed | 7.2 | — | — |
FAQ
Frequently asked questions
Does the stacked design cook the top and bottom drawers differently?
Each drawer has its own heating zone and controls, and Ninja's Sync function aligns end times. No independent public measurement of top-versus-bottom evenness was available to us.
Is 9.5 litres enough for a family?
OCU measured 2,266 g of frozen fries in total, the largest load in this ranking, which is comfortably a family portion split across both drawers.
From the same ranking
Other products in Air Fryers.
The same protocol, the same key parameter, the same set of sources.
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No. 028.1/ 10
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No. 057.3/ 10
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