Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Recommended per-occurrence limit
$1,100,000
Estimated worst-case exposure
$1,090,000
Gap vs current per-occurrence limit
$790,000
Per-person limit adequate (1=yes, 0=no)
0
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How to use this
- 1Enter current per-person bi limit ($).
- 2Enter current per-occurrence bi limit ($).
- 3Enter net worth ($).
- 4Enter annual income ($).
- 5Enter typical passengers at risk per trip.
- 6Read your recommended per-occurrence limit on the right — it updates as you type.
- 7Hit Share to keep the scenario or send it to someone.
About this calculator
State minimum auto liability limits — often written as 25/50/25 or similar — are almost always too low to protect your assets in a serious at-fault accident. A single severe injury claim, like a traumatic brain injury or long-term disability, routinely exceeds $100,000 per person in medical costs and lost wages alone. This calculator compares your current limits against a realistic exposure estimate built from your net worth, income, and the number of people you regularly drive with, then tells you the gap between what you're carrying and what a bad-case lawsuit could actually cost you, factoring in that anything above your policy limit typically comes out of your personal assets.
Worked example
Using the values the calculator loads with:
Inputs
- Current per-person BI limit: 100000 $
- Current per-occurrence BI limit: 300000 $
- Net worth: 300000 $
- Annual income: 90000 $
- Typical passengers at risk per trip: 2
Results
- Recommended per-occurrence limit: $1,100,000
- Estimated worst-case exposure: $1,090,000
- Gap vs current per-occurrence limit: $790,000
- Per-person limit adequate (1=yes, 0=no): 0
What each field means
Inputs
- Current per-person BI limit ($)
- The current per-person bi limit used in the calculation, measured in $. Starts at 100000 $ so you have a working example on load.
- Current per-occurrence BI limit ($)
- The current per-occurrence bi limit used in the calculation, measured in $. Starts at 300000 $ so you have a working example on load.
- Net worth ($)
- The net worth used in the calculation, measured in $. Starts at 300000 $ so you have a working example on load.
- Annual income ($)
- The annual income used in the calculation, measured in $. Starts at 90000 $ so you have a working example on load.
- Typical passengers at risk per trip
- The typical passengers at risk per trip used in the calculation. Starts at 2 so you have a working example on load. Accepted range: 0–7.
Results
- Recommended per-occurrence limit
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Estimated worst-case exposure
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Gap vs current per-occurrence limit
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Per-person limit adequate (1=yes, 0=no)
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
What do the three numbers in a limit like 100/300/100 mean?
The first number is the maximum paid per injured person ($100,000), the second is the maximum paid per accident across all injured people combined ($300,000), and the third is property damage coverage for the other party's vehicle or property ($100,000). If you injure three people badly, the $300,000 gets split among them, capped at $100,000 each.
Why are state minimum limits usually not enough?
Many states still require minimums like 25/50/25, set decades ago and rarely adjusted for medical cost inflation. A single ICU stay after a car accident can run $50,000-$150,000, and that's before lost wages or a lawsuit for pain and suffering. Anything above your limit becomes your personal financial responsibility, which is why this calculator flags the gap explicitly.
How does this interact with umbrella insurance?
Umbrella policies require you to carry specific minimum underlying auto liability limits, commonly 250/500/100, before they'll issue coverage on top. If your auto limits are too low, you're not just exposed on the auto side — you may not even qualify for the umbrella coverage that's supposed to be your safety net.
Does raising liability limits cost much more in premium?
No, and this surprises most people — going from 100/300/100 to 250/500/100 often costs only $5-$15 more per month, because higher limits mainly get triggered by rare, severe claims rather than everyday fender-benders. The marginal cost per additional dollar of coverage drops sharply as you move up in limits.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Auto Liability Limit Adequacy Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/auto-liability-limit-adequacy
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/auto-liability-limit-adequacy" target="_blank" rel="noopener">Auto Liability Limit Adequacy Calculator — RevenueLab</a> (2026).</p>
Source: [Auto Liability Limit Adequacy Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/auto-liability-limit-adequacy) (2026).