Voltage needed to start a car

[Vatirwar]

Hi guys. I'm a newbie car owner. Currently trying to figure out how the car's electrics work. How many volts are needed for jump-starting a car? https://reviewerst.com/jump-starters/what-is-the-minimum-voltage-needed-to-start-a-car/ they write that the voltage range can be from 11.5 to 14.2 volts. What do you think about this?

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[josby]

Jump-starting a car is really just starting a car with another car's battery, so the same voltage as a normal car battery should theoretically be enough, and that's usually 12.2 to 12.6 volts.

But, there's some voltage loss in the jumper cables and the alligator clamp connections, so higher is better.

You theoretically could jump-start from a car that is not running, but it works better to do it from a car that is running, since the running alternator will be putting out about 13.5 volts. I.e. about one volt more than the battery would if the car was off.

Also, I personally have had instances where I couldn't get a car to start from a car that was idling, but once I revved the engine up and held it at 2000 rpm or so, the dead car was able to start. That's because some alternators will not put out as much power when the engine is just at idling speed.