Calendar Spread Calculator

Calendar Spread Inputs

Option Type

Strike (same for both legs)

Short Premium (per share)

Long Premium (per share)

Contracts

Center chart around

X-Axis Range (± % around center)

Results

Net Debit (per share) $0.00

Est. Breakeven $0.00

Est. Max Profit (peak) $0.00

Max Loss (debit) $0.00

Calendar Spread Payoff (Approx.)

Two curves: solid ≈ value at short expiration; dashed ≈ prior to short expiration. (Educational approximation — real pricing depends on IV, time, and skew.)

A calendar spread (time spread) sells a near-term option and buys a longer-dated option at the same strike. Traders often use calendars to benefit from time decay in the short option while keeping longer-term exposure. This calculator provides an educational payoff profile that resembles the common “tent” shape seen in calendars.

How to Read the Chart

The payoff profile often peaks near the strike, because the short option is approaching expiration while the long option retains time value. The “prior to expiration” curve is typically lower and rounder than the “at expiration” curve.

Key Inputs

Enter your short premium and long premium (per share). Net debit = long premium − short premium. Max loss is usually limited to the debit (excluding fees). Real-world breakevens can vary due to implied volatility and spreads.

Calendar Spread FAQ

Why is this an approximation?

Calendar spreads are highly sensitive to implied volatility and time remaining. A full model needs expirations, IV, rates, and dividends. This page uses a “tent” approximation to match the typical risk profile shape.

Why do I see two curves?

At the moment the short option expires, the long option still has time value, which often creates a sharper peak. Before short expiration, both legs still have time value, so the profile is usually flatter/lower.

Is max loss limited?

In a debit calendar, max loss is commonly the net debit paid (before fees), though assignment and execution details can change outcomes.