Put-Call Parity Check Calculator
Use parity — Call − Put ≈ spot − strike — to check whether quotes on the same strike are self-consistent.
Results
Fill in the inputs and click Calculate.
- Call − Put
- –
- Spot − Strike
- –
- Parity Gap
- –
- Implied Put
- –
- Implied Call
- –
Risk disclaimer
Rates, dividends and margin are ignored here; treat it as a consistency check.
What is put-call parity?
Ignoring rates and dividends, buying a call and selling a put can replicate the underlying, so both sides should satisfy the equation.
Big gaps often reflect thin/deep-ITM quotes, not automatically an arbitrage — fees and funding still matter.
How to use
- Enter call and put premiums on the same strike.
- Enter spot and strike.
- Click Calculate for both sides, the gap, and implied counterpart premiums.
Formula
- Call − Put ≈ spot − strike
- Gap = (Call − Put) − (spot − strike)
- Implied put = call − spot + strike
Example
Spot 100, strike 100, call 6, put 4 → left 2, right 0, gap +2.
Interpret gaps with time and rates; this page is an intuition check without funding.
FAQ
Is a gap an arbitrage?
Not automatically. True parity discounts over time and nets fees — this is not trade advice.