Skip to main content

Power Bank Capacity Calculator

Lifestyle Tools

mAh to Wh, airline rules, real charges

Quick Answer

Power Bank Capacity Calculator: mAh to Wh, airline rules, real charges. Power Bank Capacity Calculator uses standard everyday life formulas to compute accurate results instantly.

mAh
%

Device to charge

mAh
Full charges for iPhone 16 Pro
4.5 times
Cell energy74.0 Wh
Usable energy62.9 Wh
Rated 5V output12580 mAh
FlightOK

Calculation steps

  1. 1Cell energy = 20000 mAh × 3.7 V = 74.0 Wh (cells are rated at 3.7V, not 5V)
  2. 2Usable after conversion loss (85%): 74.0 × 0.85 = 62.9 Wh
  3. 3Device battery = 3582 mAh × 3.9 V = 14.0 Wh → charges = 62.9 ÷ 14.0 = 4.5
  4. 4Rated capacity at 5V output ≈ 12580 mAh — this is why "20000mAh" only delivers ~12000mAh to your phone

Charges for common devices

iPhone 16 Pro
4.5 x
Xiaomi 15
3.0 x
Huawei Mate 70
3.1 x
iPad Air
2.2 x
Switch OLED
3.9 x
MacBook Air 13
1.1 x
Carry-on OK (≤100Wh, no approval needed). Power banks must go in carry-on, never checked luggage. Real-world charge counts are further reduced by cable loss and trickle phase — expect ~10% fewer than calculated.

Was this tool helpful?

How to Use

  1. Enter scenario values: fill real-life numbers into the Power Bank Capacity Calculator (defaults work for a quick try).
  2. Instant results: everything computes live, no button needed.
  3. Read the advice: results come with practical tips, reference standards and pitfalls.
  4. Compare options: adjust parameters to compare choices side by side.

Key Points

  • Power Bank Capacity Calculator is a free online everyday life tool — open and use, no sign-up.
  • All calculations run locally in your browser; your data never leaves the device.
  • Key capability: mAh to Wh, airline rules, real charges.
  • Results come with formulas and reference tables so you can verify every number.

Formula & How It Works

Power Bank Capacity Calculator formula

Power Bank Capacity Calculator uses standard everyday life formulas to compute accurate results instantly.

FAQ

How do I use the Power Bank Capacity Calculator?
Open the page and fill in the input fields — results update automatically. mAh to Wh, airline rules, real charges.
Are the results accurate?
Yes. Standard formulas and conversion factors are used and verified.
Is it free? Do I need to sign up?
Completely free. No registration, login or download required.
Does it work on mobile?
Yes. The responsive design works on phones, tablets and desktops.
Is my data saved?
No. Everything runs locally in your browser.

Related Tools

Related Guides

Source & Updates

Based on common formulas and industry conventions. Last updated: 2025-07

Last updated:

Formulas and content on this page are reviewed by the YiJianSuan team. For reference only — official sources prevail.

Maintained and periodically reviewed by the YiJianSuan editorial team — review process in ourEditorial Policy.

Cite this page: YiJianSuan. Power Bank Capacity Calculator[EB/OL]. https://www.yijiansuan.com/en/c/life/powerbank

Results provided by this tool are for reference only and do not constitute professional advice.