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Cash-Secured Put Calculator

Calculate Income, Annual Yield & Breakeven Before You Sell

Sick of spreadsheets? Missing critical numbers before hitting sell? Enter a ticker, your capital and a DTE, and our cash-secured put calculator shows the premium, how many puts your cash secures, what you'll earn per month and per year, and where you break even—all before you place the trade.

Cash-secured put strategy comparison

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Problem

Manual CSP Analysis is Broken

Missing Breakeven Calculation — Your spreadsheet doesn't calculate breakeven, so you're guessing on risk

No Real-Time Assignment Probability — You're selling puts without knowing how likely assignment is

Fragmented Data Across Tools — Premium from Tastytrade, assignment odds from Reddit, Greeks from your broker

Solution

CSP Calculator

Breakeven Price

Where you profit/lose if assigned

Downside Buffer

How far the stock can fall before you lose money

Premium Collected

Live quote for the strike nearest 2% OTM, or a labelled estimate if none

Annual Yield

Premium ÷ cash reserved, repeated for a year

Monthly Income

Premium normalized to 30 days, after fees

Contracts Covered

How many puts your capital secures

Backtest wheel strategy showing historical performance

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Try It Now: Calculate Your CSP

Monthly Income Calculator

Estimate income from selling covered calls or cash-secured puts

Sets the delta range used when you open the Strategy Analyzer. The estimate below always uses a strike about 2% out of the money.

$580.00

Need more capital to start

Try $57,000 or switch strategies

CSP vs T-Bills: How Do You Stack Up?

CSP vs T-Bills: Income Comparison

Compare cash-secured put income with T-bills at rates you enter. Both rates are your assumptions, not live market data.

Extra Income with CSPs
+$281/month
$3375 more per year = 4.0x the T-bill income
With CSPs
$375
18% annual yield
With T-Bills
$94
4.5% annual yield
12-Month Income Projection
CSPs (18% per year)
$4,500
T-Bills (4.5% per year)
$1,125
The Trade-Off
+CSPs: 4.0x higher income, but you might get assigned shares
–T-Bills: Zero risk, but $281/month less income
•CSPs work best on stocks you'd be happy to own at a discount
How CSPs Generate Extra Income
• Sell a put option on SPY (about 30 days out) at a strike you'd be happy to own
• Collect the premium up front; check real premiums in the screener below
• If SPY stays above strike → keep premium, repeat
• If SPY drops → buy shares at discount, sell covered calls

Free account. Re-run this scan with live prices any time.

Find SPY CSP Opportunities
Hypothetical: assumes you earn the premium rate above every month with no losses from assignment. Real premiums vary by stock, IV, and market conditions.
How it works

Get started in 3 simple steps

1

Enter Your Position Parameters

Ticker, capital reserved, days to expiration, and fees per contract

2

Review Your Metrics Instantly

See the strike and premium, contracts covered, monthly income, annual yield, breakeven and downside buffer

3

Check the Risk Before You Trade

Open the same setup in the Strategy Analyzer to compare strikes and see assignment probability for each contract

Using the CSP Calculator

Hypothetical scenario: Selling a CSP on AAPL

  • Current stock price: $235
  • Strike: $230 (the listed strike nearest 2% OTM)
  • Premium collected: $4.50 per share
  • DTE: 21 days
  • Capital reserved: $23,000
  • Fees: $0

Calculator shows:

  • Breakeven: $225.50 (if assigned, you own shares at this price)
  • Downside buffer: 4.0% (AAPL can fall from $235 to $225.50 before you lose money)
  • Premium: $450 per contract, 1 contract covered by $23,000
  • Monthly income: $643 ($450 normalized to 30 days)
  • Annual yield: 34.0% ($450 ÷ $23,000, repeated every 21 days)

Trader insight: Solid premium for a 4% buffer. Before selling, check the assignment probability for this contract in the Strategy Analyzer.

Key Metrics

Example: Breakeven

$225.50

Example: Downside Buffer

4.0%

Example: Premium

$450

Example: Annual Yield

34.0%

Related Resources

Cash-Secured Puts Playbook: DTE Optimization & Assignment Risk

Master CSP timing and DTE selection

Learn more

Best Stocks for Selling Cash-Secured Puts: 2026 Screening Guide

Find high-probability CSP opportunities

Learn more

Best Stocks to Sell Put Options Screener Watchlist

Curated watchlist for put selling candidates

Learn more

thinkorswim Walkthrough for Selling Cash-Secured Puts

Step-by-step platform tutorial

Learn more

Cash-Secured Puts vs Covered Calls: Which Strategy Wins?

Compare both income strategies

Learn more

How to Sell Cash-Secured Puts on Interactive Brokers

Step-by-step execution guide

Learn more

Rolling Cash-Secured Puts for Continuous Income

Extend your positions and compound returns

Learn more

How to Sell Put Options: Step-by-Step Execution Guide

Complete execution walkthrough from order entry to management

Learn more

Options Premium Tracking

Track and analyze your options premium income

Learn more

Learn Cash-Secured Put Strategies

Master the cash-secured put strategy with our comprehensive guides. Learn optimal DTE selection, rolling techniques, and how to pick the best stocks.

CSP Playbook: DTE Optimization

Complete guide to strike selection, timing, and assignment risk

Rolling Cash-Secured Puts

When and how to adjust positions for continuous income

Best Stocks for CSPs in 2026

Screening guide for high-probability put selling candidates

thinkorswim Walkthrough for CSPs

Step-by-step platform tutorial for selling cash-secured puts

Put Options Screener Watchlist

Curated watchlist for put selling opportunities

Step-by-Step Put Selling Guide

Complete execution guide from order entry to position management

Options Premium Tracking

Track and analyze your premium income across all trades

What Income Do You Need?

Use this to work backwards: enter your income goal and see what's required.

Target Income Calculator

Work backwards: set your income goal and find the required capital

Enter your target income to see requirements

Frequently Asked Questions

Everything you need to know about getting started

What's a cash-secured put?

A cash-secured put is when you sell a put option while holding enough cash to buy 100 shares at the strike price if assigned. You collect the premium immediately and keep the cash earning zero interest until assignment or expiration.

How is breakeven calculated?

Breakeven = Strike Price - Premium Collected. Example: You sell a $100 strike put and collect $3 premium. Your breakeven is $97. If the stock falls to $97, you break even. Below that, you lose money.

What's assignment probability?

Assignment probability is the chance your put finishes in-the-money at expiration (the stock closes below the strike), so the holder exercises. This calculator does not show it. The free cash-secured put screener shows one for every contract, taken from the option's market delta (or a Black-Scholes estimate when no delta is available); it is a model estimate, not a historical rate.

Why does DTE (days to expiration) matter?

Shorter DTE = Higher theta decay = More premium collected per day, but less time for recovery if stock drops. Longer DTE = Lower daily decay = Safer, but premium per day is smaller.

Can I use this calculator for puts I've already sold?

Not directly. The calculator models a new trade: it picks the listed strike nearest 2% out of the money and uses the current premium. For a put you already sold, your breakeven is still your strike minus the premium you received.

Is higher ROI always better?

No. Higher ROI usually means lower strike (deeper ITM, higher assignment risk) or shorter DTE (less time for recovery). Optimal CSP balances acceptable assignment probability, ROI matching your goals, and capital preservation.

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