I was looking up the number of electrons in a current with 1a and I keep on getting different answers. Some websites put the number at 6.24, some at 6.25 and others at 6.28 (all * 10^18)

Is there some ambiguity in regards to this question? Seems strange to get slightly different numbers.

  • \$\begingroup\$ The 6.25 number is just incorrectly rounded, and I'd guess the 6.28 number originated from either someone mixing up the 8 from 10¹⁸, or from a badly scanned/OCR'd book where the 3 got misread as an 8. If you're asking for the number of electrons in an amp (which doesn't actually make sense), rather than in a coulomb (which is probably what you meant), I wouldn't expect to find very good answers. \$\endgroup\$
    – Hearth
    Apr 8 at 15:46
  • \$\begingroup\$ 6.24e18 and 6.25e18 are likely rounding differences for the charge of an electron in the initial equation. i.e. using 1.60217663e-19 vs 1.6e-19 \$\endgroup\$
    – Michael
    Apr 8 at 15:48
  • 1
    \$\begingroup\$ There are any number of electrons in an ampere. Depends on how long that amp is flowing. Look up coulomb, instead. Mind dimensions. \$\endgroup\$ Apr 8 at 16:40

1 Answer 1


1 amp for one second is a charge of 1 coulomb. Given that a charge is made up from electrons, the total number of electrons involved in the flow of 1 amp for 1 second equals 1 coulomb divided by the charge of an electron. Given that the charge of an electron is 1.60217663 × 10-19 coulombs, then that's 6.24151 × 10+18 electrons.

Is there some ambiguity in regards to this question?

Yes there is; your question doesn't account for time because, 1 amp for one trillionth of a second (a pico second) is only 6.24151 × 10+6 electrons.

And clearly, for a long time period there are many, many more electrons shifted. In other words you can't take a snap-shot of current and ask how many electrons are involved.

  • \$\begingroup\$ And current isn't necessarily electrons at all. \$\endgroup\$
    – John Doty
    Apr 8 at 16:56
  • \$\begingroup\$ @JohnDoty Given your attempted conflation of a question yesterday and, the unwarranted comments, it begins to look like you are setting some trend or have got some kind of vendetta against me. I don't care whether current is formed from electrons or something else; the question asked about electrons and that is what I am addressing. If you have a problem with this question (or wish to conflate it) why are you not raising this under the question. That is the natural place to make this sort of observation. Beneath my answer it's just worthless words and looks like petty-minded harassment. \$\endgroup\$
    – Andy aka
    Apr 8 at 18:25

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