Put-Call Parity Calculator

Written by Great Medico

Updated September 25, 2026 •3 min read

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Small changes in rates, timing, or amounts can materially change a finance result. Put-Call Parity Calculator checks whether the entered call price, put price, present value of the strike, and spot price satisfy the basic put-call parity relationship, which makes the assumptions easier to test side by side.

What this calculator does

Put-Call Parity Calculator checks whether the entered call price, put price, present value of the strike, and spot price satisfy the basic put-call parity relationship. The visible inputs are european call option price, european put option price, present value of strike price, and spot price of the underlying asset. Its result is driven by those values, so the calculation can be reproduced or stress-tested without relying on a hidden live-data feed.

How to use it

Enter European call option price, European put option price, Present value of strike price, and Spot price of the underlying asset. Keep all monetary inputs in the same currency; the currency selector formats results and does not perform foreign-exchange conversion. Before calculating, recheck European call option price, European put option price, Present value of strike price against the source values you intend to model. Use the labels on Put-Call Parity Calculator as the source of truth and recheck any prefilled value before relying on the result.

How the calculation works

For European options with matching strike and expiration, put-call parity can be written as C + PV(K) = P + S. The calculator compares the two sides using the four values entered on the form and reports the difference. Put-Call Parity Calculator applies that relationship only to the inputs represented on its form. If the result looks surprising, verify the entered values, units, and signs before interpreting the number.

Example

If a call is $8, a put is $5, the present value of the strike is $97, and spot is $100, then C + PV(K) = $105 and P + S = $105, so the parity difference is zero. The example is a math check for Put-Call Parity Calculator; replace the sample values with your own inputs rather than treating the example as a target or recommendation.

How to interpret the result

A result near zero means the entered prices are consistent with the simplified parity identity. A nonzero gap shows the size and direction of the mismatch; it is not automatically an exploitable arbitrage after costs and market frictions. A change in the result should be traced back to the input that changed before you draw a practical conclusion.

Limitations and notes

The identity assumes comparable European-style contracts and a consistent present value for the strike. Dividends, early exercise, borrowing constraints, taxes, transaction costs, stale quotes, and different settlement conventions can create real-world differences. The safest way to reuse this calculation later is to keep the source values and date with the result.