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
Independent-shop door rate for your state band. Dealer rates are handled separately below.
Most states tax parts; several tax labor too. Pick the band closest to your county rate.
Result
What you actually pay
$945
Full repair cost
$945
Low end of quote range
$775
High end of quote range
$1,181
Converters including tax
$558
Oxygen sensors
$102
Labor
$210
Anti-theft shield
$0
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How to use this
- 1Enter converter type required.
- 2Enter converters needed (count).
- 3Enter oxygen sensors replaced (count).
- 4Enter price per oxygen sensor ($).
- 5Enter pipe, flanges, gaskets and hardware ($).
- 6Enter book labor hours (hours).
- 7Enter state shop labor rate — Independent-shop door rate for your state band. Dealer rates are handled separately below..
- 8Enter state + local sales tax on parts — Most states tax parts; several tax labor too. Pick the band closest to your county rate..
- 9Enter anti-theft shield.
- 10Enter paying method.
- 11Enter comprehensive deductible ($).
- 12Read your what you actually pay on the right — it updates as you type.
- 13Hit Share to keep the scenario or send it to someone.
About this calculator
Catalytic converter pricing splits on one question: does your state require a CARB-compliant part? California, and the states that follow its emissions rules, will not pass a vehicle fitted with a cheaper federal-spec aftermarket converter, and the compliant part frequently costs two to three times more. On top of that, converters are the most stolen part in America, so many owners are buying one after a theft — which brings a comprehensive deductible, a rental, and a good argument for a $200 shield. This calculator prices the converter by compliance tier and position, adds oxygen sensors and pipework, applies your state's labor rate and tax band, and models the insurance path plus the shield. Worked assumption for the defaults: one federal aftermarket converter at $520, one O2 sensor, 2 book hours at the $105 US-average rate, 7.25% tax — about $945 cash.
Worked example
Using the values the calculator loads with:
Inputs
- Converter type required: Direct-fit federal aftermarket — $520
- Converters needed: 1 count
- Oxygen sensors replaced: 1 count
- Price per oxygen sensor: 95 $
- Pipe, flanges, gaskets and hardware: 70 $
- Book labor hours: 2 hours
- State shop labor rate: US average — $105/hr
- State + local sales tax on parts: US average with local add-ons (~7.25%)
- Anti-theft shield: No shield
- Paying method: Paying cash
- Comprehensive deductible: 500 $
Results
- What you actually pay: $945
- Full repair cost: $945
- Low end of quote range: $775
- High end of quote range: $1,181
- Converters including tax: $558
- Oxygen sensors: $102
- Labor: $210
- Anti-theft shield: $0
What each field means
Inputs
- Converter type required
- Pick the option that matches your situation — the maths changes per option. Choices: Universal federal aftermarket — $230, Direct-fit federal aftermarket — $520, CARB-compliant aftermarket (CA and CARB states) — $1,150, OEM dealer converter — $2,100.
- Converters needed (count)
- The converters needed used in the calculation, measured in count. Starts at 1 count so you have a working example on load. Accepted range: 1–4 count.
- Oxygen sensors replaced (count)
- The oxygen sensors replaced used in the calculation, measured in count. Starts at 1 count so you have a working example on load. Accepted range: 0–4 count.
- Price per oxygen sensor ($)
- The price per oxygen sensor used in the calculation, measured in $. Starts at 95 $ so you have a working example on load. Accepted range: 20–400 $.
- Pipe, flanges, gaskets and hardware ($)
- The pipe, flanges, gaskets and hardware used in the calculation, measured in $. Starts at 70 $ so you have a working example on load. Accepted range: 0–800 $.
- Book labor hours (hours)
- The book labor hours used in the calculation, measured in hours. Starts at 2 hours so you have a working example on load. Accepted range: 0.5–10 hours.
- State shop labor rate
- Independent-shop door rate for your state band. Dealer rates are handled separately below.
- State + local sales tax on parts
- Most states tax parts; several tax labor too. Pick the band closest to your county rate.
- Anti-theft shield
- Pick the option that matches your situation — the maths changes per option. Choices: No shield, Bolt-on cat shield installed — $225.
- Paying method
- Pick the option that matches your situation — the maths changes per option. Choices: Paying cash, Comprehensive theft claim.
- Comprehensive deductible ($)
- The comprehensive deductible used in the calculation, measured in $. Starts at 500 $ so you have a working example on load. Accepted range: 0–2500 $.
Results
- What you actually pay
- 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.
- Full repair cost
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Low end of quote range
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- High end of quote range
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Converters including tax
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Oxygen sensors
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Labor
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Anti-theft shield
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
What is a CARB-compliant converter and do I need one?
It is a converter certified to California's emissions standard and carries an EO number. California and the states that adopted its rules require it for registration and inspection; installing a federal part there means failing the test and buying the correct one anyway.
Why are converters stolen so often?
They contain platinum, palladium and rhodium, and on high-clearance vehicles a thief can cut one out in under two minutes. Hybrids and trucks are hit hardest. A welded or bolt-on shield does not make it impossible, only slow enough to move on.
Can I just delete it or fit a test pipe?
No. Removing emissions equipment is a federal violation, fails inspection everywhere it is tested, throws a permanent check-engine light, and can void insurance and resale. It is also loud and smells terrible.
Where do the state labor rates come from?
They are independent-shop door rates by state band — what a non-dealer shop charges per book hour before parts. Rates cluster tightly by market cost of living, which is why the tool groups states rather than pretending each one has a single number. If you already have a quote, back out the shop's own rate and use that.
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). Cost to Replace a Catalytic Converter Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/cost-to-replace-a-catalytic-converter-calculator
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/cost-to-replace-a-catalytic-converter-calculator" target="_blank" rel="noopener">Cost to Replace a Catalytic Converter Calculator — RevenueLab</a> (2026).</p>
Source: [Cost to Replace a Catalytic Converter Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/cost-to-replace-a-catalytic-converter-calculator) (2026).