Put Call Parity Calculator

Work out put call parity instantly with clear inputs, formula shown and shareable results.

About Put Call Parity Calculator

Put-call parity states that a call minus a put equals the spot minus the discounted strike, because both sides deliver the same payoff at expiry. Any deviation is a riskless arbitrage, which is why the relationship holds tightly in liquid markets.

Formula

Put-call parity

C - P = S - Ke^(-rT)

C: Call
P: Put
S: Spot
K: Strike

Worked example

With the default values below, Put Call Parity Calculator returns Implied Put Price of $35.1855. Change any input above and every figure here is recalculated in your browser.

Inputs used

Call Priceminimum 0: 45
Spot Priceminimum 0: 1,000
Strike Priceminimum 0: 1,000
Days To Expiryaccepts 1–1,095: 60

Results

Implied Put Price: $35.1855
Present Value Of The Strike: $990.1855
Net Cost Of A Synthetic Long: $9.8145
Interest Saved By Deferring The Strike: $9.8145

Step by step

1Values used
2Put-call parity
3Implied Put Price= 35.1855
4Present Value Of The Strike= 990.1855
5Net Cost Of A Synthetic Long= 9.8145
6Interest Saved By Deferring The Strike= 9.8145

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Figures are estimates for planning only. Market returns are not guaranteed, and rates, limits and tax rules change. This is not financial or tax advice — speak to a qualified adviser before acting.
This is an estimate for general information and not professional financial, tax or legal advice. See the full disclaimer for the limits that apply to this kind of calculator.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Figures are estimates for planning only. Market returns are not guaranteed, and rates, limits and tax rules change. This is not financial or tax advice — speak to a qualified adviser before acting.

Frequently Asked Questions

Why does parity hold so well?

Because breaking it creates a risk-free profit that traders arbitrage away within seconds.

Does it work for American options?

Only approximately. Early exercise rights, mainly on puts and around dividends, break exact parity.