# Eli5: I don’t understand Black-Scholes equation for put options in this example

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Using this [calculator](https://goodcalculators.com/black-scholes-calculator/) of Black-Scholes equation for a put option, which is based on the formula:
P = ST e-rt N(-d2) – SP e-dt N(-d1)

If I use SP=62 ST=60 t= 0.25 (Years) v= 32% r= 4% d=0%

The result is \$2.71 for the put price

But I think the operation would be 62-60-2.71 and the result will be a loss of -0.71 per share

And if I use SP=62 ST=50 t= 0.25 (Years) v= 32% r= 4% d=0%

The result is \$0.32 for the put price

¿Shouldn’t it be the opposite? …. The closer you get to the SP the lower the result and the larger the gap between the SP and the ST the result should be bigger? What am I doing wrong? 🙁 I’m studying Espen Gaarder Haug Book (Option pricing formula) on my own but I cannot understand that formula when it involves a put option…

In: Economics

Not for put options. Remember that Put Options are the right to sell at a certain price.

Now what is more valuable? You can sell your shares at 60 no matter what the actual price is, or you can sell at 50?

If the price goes down to say 55, your put option to sell at 60 is valuable. The one at 50 is worthless.