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Home › Can I swap? › SR521SW vs SR63
Can I swap?

SR521SW vs SR63: can you swap them?

1The short answer2Both ways3Differences4Buy it5Learn more
  1. 1

    The short answer

    YesYes, they’re the same batterySR521SW and SR63 are two names for the exact same battery. Use either one.
    SR521SW+ 1.55V
    SR521SWAs thick as 3 credit cards stacked
    SR521SW+ 1.55V
    SR63As thick as 3 credit cards stacked
    Get SR521SW on AmazonAs an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.

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  2. 2

    Both ways round

    Can I put SR63 where SR521SW goes?Yes
    Can I put SR521SW where SR63 goes?Yes
  3. 3

    What’s different

    SR521SWSR63
    SizeAbout as wide as a pencil eraserAbout as wide as a pencil eraser Same
    ThicknessAs thick as 3 credit cards stackedAs thick as 3 credit cards stacked Same
    Power1.55 volts1.55 volts Same
    KindWatch batteryWatch battery

    Lasts longer: Same

  4. 4

    Where to buy SR521SW

    As an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.

    Our pickThe exact match, 4-packEnergizer SR521SW 1.55V Battery (4-Pack)
    Check Price on Amazon →
    Best value10-pack, handy to keep in a drawerSR521SW 1.55V Battery Value Pack (10-Pack)
    Check Price on Amazon →
    Other brandDuracell, the same batteryDuracell SR521SW / SR521SW 1.55V Battery
    Check Price on Amazon →

    Buttons open amazon.com 🇺🇸, picked from your country.

    Get SR63 on AmazonAs an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.
  5. 5

    Learn more

    About SR521SWAbout SR63Check another pair
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Questions people ask

Can I use SR63 instead of SR521SW?

Yes. SR521SW and SR63 are two names for the exact same battery. Use either one.

Can I use SR521SW instead of SR63?

Yes. SR521SW and SR63 are two names for the exact same battery. Use either one.

Which one lasts longer?

They last about the same.

All the numbers

SR521SWSR63
Diameter5.8 mm5.8 mm
Height2.1 mm2.1 mm
Nominal voltage1.55V1.55V
Typical capacity14 mAh14 mAh
ChemistrySilver oxideSilver oxide
Shelf life5 yrs5 yrs
Operating temp-10 to 60 °C-10 to 60 °C
Can I use SR63 instead of SR521SW?Yes
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Something wrong or missing? Tell us

1The short answer2Both ways3Differences4Buy it5Learn more