Value at Risk (VaR) Explained: What It Really Tells You
By Ken Chigbo, Founder, KenMacro, 18+ years across discretionary and systematic strategies, UK macro desk.
Updated 2026-05-21
The short answer
Value at Risk, or VaR, estimates the most you would expect to lose on a position or portfolio over a set time horizon at a set confidence level, under normal market conditions. A one-day 95 percent VaR of one thousand says that on 95 days out of 100 you should not lose more than that in a day. The dangerous part is the other five days. VaR tells you nothing about how bad the tail loss is when it does breach, which is exactly when it matters. Treat VaR as a rough daily gauge, never as a ceiling on what can go wrong.
What VaR actually measures
Value at Risk compresses risk into a single number: the most you would expect to lose over a chosen window, at a chosen confidence level, in normal conditions. A one-day 99 percent VaR of two thousand means that on a typical day, you should lose less than two thousand 99 percent of the time. It is popular because it is one clean figure a desk or a risk manager can track. The catch is in every word of the definition. Chosen window, chosen confidence, and crucially, normal conditions. VaR is silent on the abnormal day, and the abnormal day is the one that ends accounts.
From the desk
Knowing the term is step one. The next question is always which broker actually serves you well. The desk audits eight on regulation by entity, true cost, and honest fit.
Why VaR gives dangerous false comfort
The fatal flaw in VaR is that it says nothing about the size of the loss once the confidence threshold is breached. A 95 percent VaR is breached on roughly one day in twenty, and on that day the loss can be far larger than the VaR figure, because VaR measures the threshold, not the depth beyond it. Traders who size positions to a comfortable VaR feel protected, then meet a tail event that VaR never described. The 2008 crisis and every volatility shock since have humbled institutions that managed to VaR and ignored the tail. For a retail trader the lesson is simpler: VaR is a normal-day gauge, your stop and your position size are what handle the abnormal day.
How a trader should actually use it
Use VaR as a rough sanity check on daily exposure, not as a risk ceiling. If your one-day VaR is a large fraction of your account, you are oversized regardless of how good the setup feels. Pair it with the things VaR ignores: a hard stop on every position, a fixed small risk per trade, and a daily loss limit. The desk’s order of priority is position size and stop first, VaR as a secondary gauge, never the other way round. The number that protects you is the one you set deliberately, not the one a normal distribution estimates.
Frequently asked
What does Value at Risk mean in simple terms?
It is an estimate of the most you would expect to lose over a set period at a set confidence level, under normal conditions. A one-day 95 percent VaR of one thousand means on 95 days out of 100 you should not lose more than that in a day. It says nothing about how bad the other five days get.
What is the main weakness of VaR?
It is silent on tail risk. VaR measures the threshold loss at a confidence level, not the depth of the loss when that threshold is breached. On the breach day the loss can be far larger than the VaR number, which is exactly when risk matters most. Managing to VaR and ignoring the tail is how institutions blow up.
Should a retail trader use VaR?
As a rough daily exposure gauge, yes. As a risk ceiling, no. A hard stop on every trade, fixed small risk per trade, and a daily loss limit do the real protective work. VaR is a normal-day estimate, your stop and size handle the abnormal day that VaR cannot describe.
Educational analysis only, not financial advice. KenMacro has commercial partnerships with the brokers referenced and may earn a commission if you open an account.
From the desk, free
Get the macro framework the desk actually trades
The same regime-first framework behind every call on this site, plus the weekly macro brief. Free. No spam, unsubscribe anytime.
Continue reading
From the desk
Where this gets traded
Reading the macro driver is half of it. The other half is an account that holds execution when the driver actually moves the tape. See the KenMacro desk guide to the best brokers for macro traders.
Read the desk guide →