Online service that computes implied volatility
"My broker (thinkorswim) offers this from the platform's trade tab.  I believe this feature isn't crippled in the PaperMoney version which is effectively a ""free online service.""" remember that IV is literally the volatility that would be present to equate to the latest price of a particular option contract, assuming the Black-Scholes-Merton model. Yahoo's free finance service lists the IV for all the options that it tracks.
"Their algorithm may be different (and proprietary), but how I would to it is to assume that daily changes in the stock are distributed normally (meaning the probability distribution is a ""bell curve"" - the green area in your chart).  I would then calculate the average and standard deviation (volatility) of historical returns to determine the center and width of the bell curve (calibrating it to expected returns and implied volaility based on option prices), then use standard formulas for lognormal distributions to calculate the probability of the price exceeding the strike price. So there are many assumptions involved, and in the end it's just a probability, so there's no way to know if it's right or wrong - either the stock will cross the strike or it won't." Historical volatility of a stock is going to be based on past performance, basically its current trend.  That can be useful, but really is no indication of how it will perform in the future.  Especially with a big swing in the market. Now if you're talking about implied volatility (IV) of an options contract, that's a little different.  IV is derived from an option’s price and shows what the market “implies” about the stock’s volatility in the future. Thus it is based on the actions of active traders and market makers.  So, it gives you a bit more insight into what's going on, but at times has less to do with fundamentals. I guess a good way to think of IV based on options contracts is as an educated opinion, of the market as a whole, with regards to how much that stock could likely move over a period of time (options expiration). Also note that IV represents the potential for a stock to move, but it does not forecast direction. I don't know of any studies off the top of my head, but I'm sure there have been plenty. "I strongly suggest you read up the Option Greeks. You can be right about a stocks price movement and still not make money b/c other factors come into play from time or volatility. For a ""free"" option hedge you can look at collars. Buying puts and selling calls to offset the debit you pay for the transaction. Ex: AAPL is 115, You buy the 110 puts and sell the 120 calls. This gives you a collar around he current price. Your hedged below 110 and can still participate in upside move to 120. Also look into time value. Time decays exponentially in the last 30 days. If you are long this hurts you, if you are short(selling) this is good. Be sure to take this into account. Delta: relation of the option to the underlying stock move on a .01-1 scale, .50 is ""normal."" Deep in the money options have higher deltas. It is possible other factors can offset this delta move. This is why people will lose money on earnings plays even though they are right.  EX: Say you buy an AAPL call at 120, earnings comes out and the stock goes to 121. Even though you are ""in the money"" your contract may still have less value than what you paid because of VOLATILITY collapse. The market place knows earnings move a stock and that is factored into the price of the options expected volatility. As mentioned watch out for dividend dates. Always be aware of dividend dates and earnings dates and if your contract is going to cover one of these events. Interest rates have an effect as well but since the Fed has near 0 rates there is little impact at the present. Though this could certainly change if the fed starts raising rates. Research the Black Scholes Pricing model. Whenever you trade always think about what the other guys is thinking. Sometimes we forget their is someone else on the other side of my trade that thinks essentially the exact opposite of me. Its a zero sum game. As far as choosing strikes you can look at calculating the At THe money straddle to see if the options are ""cheap"" [stock Price * Implied Volatility (for 30, 60, 90 days Depending on your holding period)* Sq root of days to expiration] / 19 (which is sq root of days/yr) Add and subtract this number to the current stock price to give you an approximate 1 standard deviation of expected price movement. Keeping with our example. AAPL at 115, lets say your formula spits out a 6; therefore price range is expected to be 109 to 121 for the time period. Helpful for selling options, I would sell the 122  call or the 108 puts. Hope this helps. Start small and get a feel for things." It is a fool's errand to attribute abnormal option volume or volatility to any meaningful move in the stock. One side of the chain is frequently more expensive than the other. The relationship between historical volatility and implied volatility is dubious at best, and also a big area of study. You'll need to find out in what format MoneyStrands expects the data.  A .qif or an .ofx file may not be the answer. i will not calculate it for you but just calculate the discounted cash flow (by dividing with 1.1 / 1.1^2 / 1.1^3   ...)of each single exercise as stated and deduct the 12.000 of the above sum.  in the end compare which has the highest npv Moody's is now Mergent Online. It's no longer being printed, and must be accessed digitally. In order to browse the database, check with your local public library or university to see if you can get access. (A University will probably require you to visit for access).  Another good tool is Value Line Reports. They are printed information sheets on public companies that are updated regularly, and are convenient for browsing and for comparing securities. Again, check your local libraries.  A lot of the public information you may be looking for can be found on Yahoo Finance, for free, from home. Yahoo finance, will give financial information, ratios, news, filings, analysis, all in one place. I use Yahoo Finance to plot my portfolio value over time. Yahoo Finance uses SigFig to link accounts (I've linked to Fidelity), which then allows you to see you exact portfolio and see a plot of its historical value. I'm not sure what other websites SigFig will allow you to sync with, but it is worth a try. Here is what the plot I have looks like, although this is slightly out of date, but still gives you an idea of what to expect.