Why call option price increases with higher volatility
The mathematics make it easier to understand why this is the case. Using very bad shorthand, d1 and d2 are inputs into N(), and N() can be expressed as the probability of the expected value or the most probable value which in this case is the discounted expected stock price at expiration. d1 has two σs which is volatility in the numerator and one in the denominator.  Cancelling leaves one on top.  Calculating when it's infinity gives an N() of 1 for S and 0 for K, so the call is worth S and the put PV(K).  At 0 for σ, it's the opposite. More concise is that any mathematical moment be it variance which mostly influences volatility, mean which determines drift, or kurtosis which mostly influences skew are all uncertanties thus costs, so the higher they are, the higher the price of an option. Economically speaking, uncertainties are costs.  Since costs raise prices, and volatility is an uncertainty, volatility raises prices. It should be noted that BS assumes that prices are lognormally distributed.  They are not.  The closest distribution, currently, is the logVariance Gamma distribution. Understanding the BS equation is not needed. What is needed is an understanding of the bell curve.   You seem to understand volatility. 68% of the time an event will fall inside one standard deviation. 16% of the time it will be higher, 16%, lower.  Now, if my $100 stock has a STD of $10, there's a 16% chance it will trade above $110. But if the STD is $5, the chance is 2.3% per the chart below. The higher volatility makes the option more valuable as there's a highr chance of it being 'in the money.' My answer is an over simplification, per your request. I agree that high volatility just means the underlying stock price fluctuates more, and it does not imply if the stock is going up or down. But a high volatility in the price of an underlying also means that there is a higher chance that the underlying price could reach extreme prices (albeit in either direction). However, if you purchased a call option then if the underlying price reached an extremely high value, then you will be richly rewarded. But if the underlying price reached an extremely low value, you won't lose any more than the initial premium that you paid. There is no additional risk on your side, it's capped to the premium that you paid for the call option. It's this asymmetric outcome (Heads - I win, Tails - I don't lose) combined with high volatility that means that call options will increase in value when the underlying price becomes more volatile. If the optionality wasn't there then the price wouldn't be related to the volatility of the underlying. But that would be called a Future or a Forward :-) When volatility is higher, the option is more likely to end up in-the-money. Moreover, when it ends up in-the-money, it is likely to be over the strike price by a greater amount. Consider a call option. With high volatility, moves in the stock price are big - both up moves and down moves. If the stock moves up by a lot, the call option holder will benefit greatly. On the other hand, when the stock moves down, below a certain point the option holder does not care how big a down move the stock has. His downside is limited. Hence, the value of the option is increased by high volatility. I know everyone who searches this is looking for this answer. Bump so people are able to get this concept instead of looking all over the web for it. The entire premise of purchasing a call option is your expectation that the prices will rise. So even though there is a possibility of prices falling, you wouldn't mind paying higher premiums in a volatile market  for a call option because you're bullish and are expecting the volatility to eventually turn out in your favour i.e. prices to rise Let's say a stock trades at $100 right now, and you can buy a $100 call option. When you buy the call option (and the money you paid is gone), one of two things can happen: The share price goes up, or the share price goes down.  If the share price goes up, you profit. If the share price goes down, you don't lose! Because once the shares are below $100, you don't exercise the call option, and you don't lose any money.  So if you have a share that is rock solid at $100, you don't make money. If you have a share where the company owner took some ridiculous risk, and the shares could go to $200 or the company could go bankrupt, then you have a 50% chance to make $100 and a 50% chance to not lose anything. That's much more preferable.
Changes in implied volatility are caused by many things, of course, and it is tough to isolate the effect you are describing, but let's try to generalize for a moment. Implied volatility is generally a measure of how much expect uncertainty there is about the future price of the stock.  Uncertainty generally is higher in periods including earnings announcements because it is significant new information about the company's fortunes can make for significant changes in the price. However, you could easily have the case where the earnings are good and for some reason the market is very certain that the earnings will be good and near a certain level.  In that case the price would rise, but the implied volatility could well be lower because the market believes that there will be no significant new information in the earnings announcement. In the scenario you describe, and really, in any scenario, by the nature of how option contracts work: a higher strike put will necessarily be more expensive than the lower strike put (everything else being equal). the lower strike call will necessarily be more expensive than the higher strike call (everything else being equal). In put options, the buyer has the right to sell stock for the strike price. So the higher the strike price, the more money the buyer of the put option can make by selling the shares of stock at a higher price. In call options, it's the exact opposite: buyers of the call option have the right to buy stock at the strike price. The lower the strike price, the better for the buyer: they have the right to buy stock for a lower amount of money. So it must be worth more. [This is a company's (TradingView.com) customer subscription levels.](https://i.imgur.com/1YIPzOn.gif)  Why do they charge a higher price when customers pay monthly? Monthly increases short term cash flow, right? Why do you think they make prices in such a way that it incentivizes customers to be billed every 2 years? It could be that the contracts were bought at cheaper prices such as $.01 earlier in the day. What you see there with the bid and ask is the CURRENT bid and CURRENT ask. The high ask price means there is no current liquidity, as someone is quoting a very high ask price just in case someone really wants to trade that price. But as you said, no one would buy this with a better price on a closer strike price. The volume likely occurred at a different price than listed on the current ask. Consider the price history to be the sum of short term movements and long term movements. If you hold a stock for a long time you will benefit (or lose) from its long term movement.  If a sufficiently large and very good short term trader existed he would tend to reduce short term volatility, eventually to nearly zero. At that point, the price would rise gently over the course of the day in line with the long term variation in price. Presumably robot traders will increase the time horizon of their trades when they have exhausted the gains they can make from short term trades. Option liquidity and underlying liquidity tend to go hand in hand. According to regulation, what kinds of issues can have options even trading are restricted by volume and cost due to registration with the authorities. Studies have shown that the introduction of option trading causes a spike in underlying trading. Market makers and the like can provide more option liquidity if there is more underlying and option liquidity, a reflexive relationship. The cost to provide liquidity is directly related to the cost for liquidity providers to hedge, as evidenced by the bid ask spread. Liquidity providers in option markets prefer to hedge mostly with other options, hedging residual greeks with other assets such as the underlying, volatility, time, interest rates, etc because trading costs are lower since the two offsetting options hedge most of each other out, requiring less trading in the other assets. Option prices are computed by determining the cost of obtaining the option returns using a strategy that trades the underlying asset continuously.  It sounds like what you are describing is rapidly trading the option in order to obtain returns similar to those of the stock.  The equality goes both ways.   If the option is appropriately priced, then a strategy that replicates stock returns using the option will cost the same as buying the stock. Because you can't trade continuously, you won't actually be able to replicate the stock return, and it may seem like you are making arbitrage profit (puts may seem abnormally expensive), but you do so by bearing tail risk (i.e., selling puts loses more money than owning the associated stock if an unusually bad event occurs). Long convexity is achieved by owning long dated low delta options. When a significant move occurs in the underlying the volatility curve will move higher. Instead of a linear relationship between your long position and it's return, you receive a multiple of the linear return. For example: Share price $50 Long 1 (equals 100 shares) contract of a 2 year 100 call Assume this is a 5 delta option If the stock price rises to $70 the delta of the option will rise because it is now closer to the strike. Lets assume it is now a 20 delta option. Then  Expected return on a $20 price move higher, 100 shares($20)(.20-.05)=$300 However what happens is the entire volatility surface rises and causes the 20 delta option to be 30 delta option. Then The return on a $20 price move higher, 100 shares($20)(.30-.05)=$500 This $200 extra gain is due to convexity and explains why option traders are willing to pay above the theoretical price for these options. Well the thing to understand about HFT is that the volume levels heavily affect not just the earnings but also the ecosystem. HFT is almost always liquidity constrained so the volume and volatility is going to affect the overall profitability of the strategy since less of these things means fewer and smaller trading opportunities.  Since 2008 volume and volatility have been heavily negatively correlated with risk-on/risk-off. During risk-off periods investors seem to panic and trading hits a frentic pace. This describes late 2008 and more recently August 2011. Even in 2012 the highest volume/volatility period was in May when the Euro deals were in danger. Risk-on environments tend to be marked be calm, orderly buying.  Second the dark pool issue is bringing liquidity out of the lit markets where HFT normally makes its money. The primary reason for this trend is that dark pools are allowed to offer sub-penny quotes whereas lit exchanges are not. Because of this arbitrary regulatory constraint most of the time dark pools are going to offer better prices, especially on thick book securities.  But beyond that the level of volume effects some HFT players more heavily then others. Imagine all the HFT firms as a pride of lions. When volume is high and liquidity is flowing it's like the pride has brought in a giant water buffalo. The biggest, baddest cats eat first, but there's still food left for the cubs after they're finished feeding.  But if the pride only brings in say a baby gazelle the alpha cats will eat everything and the runts will go hungry. That basically describes what's happening now. A firm like RennTech or GETCO will make less money in a low volume environment, but still do fine. Marginal firms like Eladian will lose the ability to make any money.  Since the marginal firms need the press and the dominant firms tend to be more secretive than the NSA, you'll tend to read more about the former than the latter. That is mostly true, in most situations when there are more buy orders than sell orders (higher buy volume orders than sell volume orders), the price will generally move upwards and vice versa, when there are more sell orders than buy orders (higher sell volume orders than buy volume orders), the price will generally move downwards. Note that this does not always happen, but usually it does. You are also correct that for a trade to take place a buyer has to be matched with a seller (or the buy volume matched with the sell volume). But not all orders get executed as trades. Say there are 50 buy orders in the order book with a total volume of 100,000 shares and the highest buy order is currently at $10.00. On the other side there are only 10 sell orders in the order book with total volume of 10,000 shares and the lowest sell order is currently $10.05. At the moment there won't be a trade unless a new buyer or seller enters the market to match the opposing side, or an existing order gets amended upper or lower to match the opposing side. With more demand than supply in the order books what will be the most likely direction that this stock moves in? Most likely the price will move upwards. If a new buyer sees the price moving higher and then looks at the market depth, they would most likely place an order closer to the lowest sell order than the current highest buy order, say $10.01, to be first in line in case a market sell order is placed on the market. As new buy orders enter the market it drives the price higher and higher until the buy orders dry up. Since near-term at-the-money (ATM) options are generally the most liquid, the listed implied vol for a stock is usually pretty close to the nearest ATM volatility, but there's not a set convention that I'm aware of.  Also note that for most stocks, vol skew (the difference in vol between away-from-the-money and at-the-money options) is relatively small,  correct me if I'm wrong, IV is the markets assessment that the stock is about 70% likely (1 Standard Deviation) to move (in either direction) by that percent over the next year. Not exactly.  It's an annualized standard deviation of the anticipated movements over the time period of the option that it's implied from.  Implied vol for near-term options can be higher or lower than longer-term options, depending on if the market believes that there will be more uncertainty in the short-term.  Also, it's the bounds of the expected movement in that time period. so if a stock is at $100 with an implied vol of 30% for 1-year term options, then the market thinks that the stock will be somewhere between $70 and $130 after 1 year.  If you look at the implied vol for a 6-month term option, half of that vol is the range of expected movement in 6 months. Volatility typically decreases when stocks rise except pending news events or fast markets.  It has a great impact of the premium of the option. "The strategy is right. As pointed out by you, will the "" volatility cause the premium on the price of the options to be too high to make this worthwhile"" ... this is subjective and depends on how the markets feels about the volatility and the trend ... ie if the market believes that the stock will go up, the option at 45 would cost quite a bit less. However if the market believes the stock would go down, the option at 45 would be quite high [and may not even be available].   There is no generic right or wrong, the strategy is right [with out without putting dividend into equation] it depends what options are available at what prices." In this situation I would recommend figuring out about what you would need to pay in taxes for the year.  You have two figures (your salary and dependents) , but not others.  Will you contribute to a 401K, do you itemize deductions, etc...  If things are uncertain, I would figure my taxes as if I took the standard deduction.   For argument's sake let's assume that comes out to $7300.  I would then add $500 on to my total to cover potential increases in taxes/fees.  You can adjust this up or down based on your ability to absorb having to pay or the uncertainty in your first calcuation. So now $7800, divide by 26 (the amount of paychecks you receive in a year) = $300 Then I would utilize a payroll calculator to adjust my exemptions and additional witholding so my federal withholding is as close as possible to this number.   Or you can sit with your payroll department and do the same. "Whoops, responded to the wrong person. Reposting for you in case you didn't see it.       Here's a source for the $3.7 trillion number.      http://www.bloomberg.com/news/2011-12-08/u-s-municipal-bond-market-28-larger-than-estimated-federal-reserve-says.html    It's not 'incorrect data'.        EDIT:  Furthermore, in order to know the ""extent"" of the crime (your own admission) we NEED to know the size of the entire market otherwise you can't have any perspective or determine extent.  So there's no reason it shouldn't be mentioned in the article."