EcoFlow DELTA 2 Max vs EcoFlow DELTA Pro: manufacturer-published specifications compared

EcoFlow DELTA 2 Max vs EcoFlow DELTA Pro: cheaper per watt-hour vs longer cycle rating

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Specifications checked against manufacturer pages on 2026-08-24.

The EcoFlow DELTA 2 Max (2,048 Wh, 2,400 W) and the EcoFlow DELTA Pro (3,600 Wh, 3,600 W), compared on the figures their makers publish. On the normalized ratios, the DELTA 2 Max costs less per watt-hour ($0.63/Wh vs $0.78/Wh); the DELTA Pro is rated for more cycles (3,500 vs 3,000).

In short. The DELTA 2 Max leads on cost per watt-hour ($0.63/Wh vs $0.78/Wh), watt-hours per pound (41.0 Wh/lb vs 36.4 Wh/lb) and continuous watts per dollar (1.85 W/$ vs 1.29 W/$). The DELTA Pro leads on rated cycle life (3,500 vs 3,000). 2 of 6 measures tie or are not comparable.

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Check the current price

EcoFlow DELTA ProEcoFlow DELTA Pro on Amazon

Links go to the exact base unit we compared, not a bundle. Amazon prices change daily.

We do not link the DELTA 2 Max: we could not confirm a listing for the exact base unit, and we do not link a guess.

Specifications, side by side

Numbered notes below the table give the source location or a caveat for figures that need one; check marks mark the better figure where one can be judged; “Manufacturer does not state” means absent from that maker’s page as of its check date listed under Sources. UPS switchover is how long the outlets go dark when grid power drops.

Specification EcoFlow DELTA 2 Max EcoFlow DELTA Pro
Rated capacity 2,048 Wh1 3,600 Wh2 ✓
Usable capacity (calculated)* 1741–1843 Wh 3060–3240 Wh
Continuous AC output 2,400 W3 3,600 W4 ✓
Surge output 4,800 W5 7,200 W6 ✓
Full recharge from wall Manufacturer does not state (0–80% in 66 min)7 162 min8
Cell chemistry LFP (LiFePO4)9 LFP10
Rated cycle life 3,000 cycles to 80%+11,12 3,500 cycles to 80%13,14 ✓
UPS switchover <20 ms15 Manufacturer does not state
Expandable Yes, up to 6,144 Wh16,17 Yes, up to 25,000 Wh18,19
Max solar input 1,000 W20 1,600 W21 ✓
Max AC charging input 1,800 W22 3,000 W23 ✓
AC outlets 624 ✓ 525
Highest USB-C port 100 W26 100 W27
App control Yes28 Manufacturer does not state
Stated noise 30 dB29 48–60 dB30
Warranty 5 years31 3 years32
Weight 50 lb33 ✓ about 99 lb34
Manufacturer list price when checked $1,29935 ✓ $2,79936

* Calculated: rated capacity × an assumed 85–90% conversion efficiency; no maker publishes a usable figure.

Notes on the figures

  1. DELTA 2 Max, rated capacity: Listed under “Capacity” on the manufacturer’s spec sheet for the base unit.
  2. DELTA Pro, rated capacity: Rated capacity of the base unit before any extra batteries are added.
  3. DELTA 2 Max, continuous output: Total continuous AC output across all six outlets.
  4. DELTA Pro, continuous output: Rated continuous AC output across all outlets combined; an X-Boost mode supports resistive devices up to 4,500 W.
  5. DELTA 2 Max, surge: Conventional surge rating; the page separately markets a boost mode of 3400 W for resistive loads.
  6. DELTA Pro, surge: Conventional surge rating; the page separately markets a boost mode of 4500 W for resistive loads.
  7. DELTA 2 Max, recharge: The manufacturer does not state a full 0-100% wall-recharge time. It states an 80% charge in 1.1 hours on AC alone, and 80% in 43 minutes when 1800 W AC input is combined with 600 W of solar input.
  8. DELTA Pro, full recharge: Full recharge from a standard wall outlet at 1,800 W takes 2.7 hours (162 minutes), the figure we use; the maker also states 1.7 hours at an EV charging station (3,400 W) and 1.9 hours with dual AC plus solar charging.
  9. DELTA 2 Max, cell chemistry: Listed under “Battery Chemistry” on the manufacturer’s spec sheet.
  10. DELTA Pro, cell chemistry: LFP is lithium iron phosphate chemistry.
  11. DELTA 2 Max, cycle life: Rated to the point where at least 80% of original capacity remains.
  12. DELTA 2 Max, cycle life: The manufacturer writes “80+%”, meaning 80 percent or more of the original capacity remains after the rated cycles.
  13. DELTA Pro, cycle life: To 80% of original capacity; the same specification line also states 6,500 cycles to 50% capacity.
  14. DELTA Pro, cycle life: Remaining-capacity endpoint paired with the 3,500-cycle figure; the maker also states 6,500 cycles to a 50% endpoint.
  15. DELTA 2 Max, UPS switchover: Upper bound. The page states the auto-switch to battery power happens in under 20 milliseconds.
  16. DELTA 2 Max, expandable: Capacity expands by attaching up to two extra batteries.
  17. DELTA 2 Max, expandable: Maximum system capacity with two extra batteries attached.
  18. DELTA Pro, expandable: Each unit supports up to two DELTA Pro Smart Extra Batteries or Smart Generators.
  19. DELTA Pro, expandable: Upper bound for a whole-system setup that requires two DELTA Pro units with extra battery packs plus two Smart Generators; a single DELTA Pro with two extra batteries reaches 10.8 kWh.
  20. DELTA 2 Max, solar input: Total across the two solar input ports; a single port accepts up to 500 W.
  21. DELTA Pro, solar input: Maximum solar charging input; the solar input voltage range is 11-150 V at up to 15 A.
  22. DELTA 2 Max, AC input: Maximum AC wall-charging input.
  23. DELTA Pro, AC input: Maximum AC input at 240 V; on a standard 120 V outlet the maximum is 1,800 W.
  24. DELTA 2 Max, AC outlets: Six household AC outlets sharing a 2400 W total output.
  25. DELTA Pro, AC outlets: The specifications table lists five AC outlets; the page’s FAQ separately counts four 20 A household AC outlets among the unit’s output ports.
  26. DELTA 2 Max, USB-C: Per port; the unit has two USB-C ports.
  27. DELTA Pro, USB-C: Per port; the unit has two USB-C ports.
  28. DELTA 2 Max, app: Controlled through the EcoFlow app; the spec sheet lists Wi-Fi and Bluetooth connectivity.
  29. DELTA 2 Max, noise: Measured at a distance of approximately 20 inches, with low charging input and a 500 W output load, per the page’s own footnote.
  30. DELTA Pro, noise: Measured at a 1-meter distance; the level varies with the wattage flowing in or out of the battery and with temperature.
  31. DELTA 2 Max, warranty: The maker markets this as an “Extensive 5-Year Warranty” on the product page.
  32. DELTA Pro, warranty: EcoFlow states a 3-year standard warranty; a 2-year extension requires EcoFlow App registration, so per our policy we count the base three years.
  33. DELTA 2 Max, weight: Net weight of the base unit; the same spec sheet lists the metric weight as 23 kg.
  34. DELTA Pro, weight: Approximate net weight stated by the manufacturer.
  35. DELTA 2 Max, price: List price; a sale price of $1,049.00 was shown.
  36. DELTA Pro, price: List price; a sale price of $1,899 was shown, and a members-only final price of $1,799 was also advertised.

The same specs, normalized

Ratios, so the bigger unit does not win by default.

Measure DELTA 2 Max DELTA Pro
Cost per watt-hour $0.63/Wh ✓ $0.78/Wh
Watt-hours per pound 41.0 Wh/lb ✓ 36.4 Wh/lb
Surge headroom 2.00× 2.00×
Recharge rate Not comparable — EcoFlow does not state a full-recharge time for the DELTA 2 Max.
Rated cycle life 3,000 3,500 ✓
Continuous watts per dollar 1.85 W/$ ✓ 1.29 W/$

Definitions and direction of each ratio: How we verify.

What each one runs, for how long

Appliance DELTA 2 Max DELTA Pro
Full-size refrigerator
150 W, 900 W start, 35% duty · eff. 70%–87%		 27–34 hr 2.0–2.5 days
Mini fridge
70 W, 400 W start, 30% duty · eff. 70%–82%		 2.8–3.3 days 5.0–5.9 days
CPAP without humidifier
40 W · eff. 70%–82%		 36–42 hr 2.6–3.1 days
CPAP with heated humidifier
95 W · eff. 70%–82%		 15–18 hr 27–31 hr
Gas furnace blower
400 W, 1600 W start, 40% duty · eff. 80%–87%		 10–11 hr 18–20 hr
1/3 hp sump pump
500 W, 1800 W start, 15% duty · eff. 85%–90% / 80%–87%		 23–25 hr 38–42 hr
Router and modem
20 W · eff. 70%–82%		 3.0–3.5 days 5.2–6.1 days
Laptop
60 W · eff. 70%–82%		 24–28 hr 1.8–2.1 days
1500W space heater
1500 W · eff. 85%–90%		 about 1.2 hr 2.0–2.2 hr

Calculated, not measured: hours = rated Wh × efficiency ÷ (appliance W × duty); assumptions on How we verify. “Unlikely to start”: start-up surge exceeds the stated surge rating.

What the differences mean

Price per watt-hour. At the list prices we checked, the DELTA 2 Max costs $0.63/Wh against $0.78/Wh for the DELTA Pro. At list the DELTA 2 Max is $1,500 cheaper ($1,299 vs $2,799) for 2,048 Wh vs 3,600 Wh. Prices move with sales; the ratio moves with them.

Weight for the capacity. The DELTA 2 Max carries 41.0 Wh/lb against 36.4 Wh/lb for the DELTA Pro. Both are cart-or-two-people units; the difference matters if the unit moves between car, porch and basement.

Cycle rating. The DELTA Pro is rated for 3,500 cycles against 3,000 for the DELTA 2 Max, both to the same remaining-capacity threshold — otherwise we would not compare them. At one full cycle a week the difference is measured in years, not months; at occasional outage use neither limit is reached.

Output for the money. 1.85 W/$ on the DELTA 2 Max against 1.29 W/$ on the DELTA Pro: this is the ratio to read if your outage plan is one big appliance, not many small ones.

Which one, and for whom

On normalized measures the DELTA 2 Max leads on cost per watt-hour ($0.63/Wh vs $0.78/Wh), watt-hours per pound (41.0 Wh/lb vs 36.4 Wh/lb) and continuous watts per dollar (1.85 W/$ vs 1.29 W/$). The DELTA Pro answers on rated cycle life (3,500 vs 3,000). The deciding figure is the one your own outage will test first:

  • CPAP overnight. Switchover: DELTA 2 Max under 20 ms, DELTA Pro no UPS figure stated. A 40 W CPAP runs roughly 36–42 hr on the DELTA 2 Max and 2.6–3.1 days on the DELTA Pro. Both run the night; the DELTA Pro states no UPS figure, which matters more overnight than the hour difference.
  • Keeping a refrigerator cold. The compressor has to start before hours matter. The DELTA 2 Max states a 4,800 W surge rating; the DELTA Pro states a 7,200 W surge rating. A full-size refrigerator needs about 900 W to start.
  • A multi-day outage with a generator or solar to recharge from. Full recharge: DELTA 2 Max 0–80% in 66 min (no full-charge time stated), DELTA Pro 162 min. These are not comparable: EcoFlow states no full-charge time for the DELTA 2 Max.

Check the current price

EcoFlow DELTA ProEcoFlow DELTA Pro on Amazon

Links go to the exact base unit we compared, not a bundle. Amazon prices change daily.

We do not link the DELTA 2 Max: we could not confirm a listing for the exact base unit, and we do not link a guess.

Related reading

A 2,048–3,600 Wh battery cannot do what a gasoline generator does — the runtime table shows a 1,500 W space heater emptying either unit in 1.2–2.2 hr — but it also cannot poison a household. How often gasoline generators kill indoors — and how the official count keeps being revised — is documented in our CPSC revision matrix, and this page puts every verified unit on the same refrigerator scenario.

Ordering before a storm? Check the arrival date at checkout — a unit that ships tomorrow can beat a better one that ships next week. Amazon Prime includes fast delivery on eligible items and starts with a free trial; we earn a commission if you join.

Sources and method

Published specifications only; no bench tests. Method: How we verify. More: Comparisons.