An insulated-wire quote applies to the accepted cable's whole weight. A stripped-copper estimate applies only to the recovered copper, not the insulation. If 10 pounds of cable yields 7 pounds of copper, price the stripped option using 7 pounds. The calculator uses estimated recovery by wire type; a weighed sample is more specific.
Compare the recovered-metal payout with the as-is quote, then subtract the value of stripping time and any equipment costs. At example rates of $1 per pound as-is and $2 per pound for accepted stripped copper, that sample gives $10 as-is or $14 stripped before labor. Spending $5 worth of time would leave stripping $1 behind. These are example rates, not current quotes.
This is a value comparison, not a cable-length or engineering weight calculator. Fiber-optic cable and platinum thermocouple wire need different material identification and buyers; they should not be entered as ordinary copper wire. Ask the yard which grade it will accept before processing a load.