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Glossary

Watt-hour (Wh)

A unit of energy capacity. A 100 Wh battery delivers 100 watts for one hour, 50 watts for two, etc. The canonical spec for laptop and power-station batteries; airlines cap carry-on at 100 Wh.

Watt-hours measure total energy. Wh = (mAh × V) / 1000. A 5,000 mAh / 7.6 V phone battery is 38 Wh.

Practical reference points

  • Smartphone — 14–22 Wh.
  • Tablet — 30–45 Wh.
  • Ultrabook — 50–80 Wh.
  • Gaming laptop — 90–99.9 Wh (limited to stay under FAA carry-on cap).
  • Power station — 250–4000+ Wh.

Why Wh beats mAh for cross-device comparison

mAh only makes sense at a known voltage. A 10,000 mAh phone power bank at 3.7 V (37 Wh) is half the energy of a 10,000 mAh laptop battery at 7.4 V (74 Wh). For honest cross-product comparison, always convert to Wh.

Buyer context

How to use Watt-hour (Wh) in a real comparison

A unit of energy capacity. A 100 Wh battery delivers 100 watts for one hour, 50 watts for two, etc. The canonical spec for laptop and power-station batteries; airlines cap carry-on at 100 Wh. In practice, this is most useful as one part of a decision rather than a standalone quality badge. Compare it alongside the workload, room, ecosystem, budget, and ownership constraints that apply to you; the strongest published figure is not automatically the best outcome for every buyer.

What to check next

On vsMars, read together so the value has product-specific context. It is especially relevant in .

Avoid the one-number trap

Manufacturers can describe the same capability under different conditions. Compare like-for-like variants, check the unit and test condition where available, and use a head-to-head page to see whether a measurable difference is material for your own use.

vsMars presents structured catalog values to make trade-offs legible. The linked product and spec pages are the right place to inspect the underlying values before buying.

Where this matters

Categories that use watt-hour (wh)

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