Property Tax Calculator
✦ Finance & MoneyUse this property tax calculator to estimate your annual and monthly tax from market value, assessment ratio and the rate on your bill — in percent, mills, or per $100 or $1,000. As a property tax estimator in reverse, it finds your effective rate from a known bill.
- ✓ Calculated in your browser
- ✓ Nothing you type is stored
- ✓ No sign-up required
- ✓ Formula and sources shown
The formula
Assessed value, less exemptions, times the effective rate — with the four rate notations converted
assessed = market_value × (assessment_ratio / 100)
taxable = max(0, assessed − exemption)
annual = taxable × effective_rate
monthly = annual / 12
eff_on_mkt = annual / market_value
Rate conversions:
effective % → mills: r × 1000
effective % → per $100: r × 100
effective % → per $1,000: r × 1000
mills → effective %: mills / 1000The assessment ratio (often 80–100%) converts market value to the taxable base before the rate is applied. Exemptions — homestead, senior, veteran and others — reduce the taxable value, not the market value. All four common rate notations (effective %, mills, $ per $100, $ per $1,000) are equivalent; the calculator converts between them automatically. Reverse mode solves for the effective rate from a known annual bill. Nothing here changes by tax year.
Calculating it by hand
- Choose a mode: Calculate my tax (from a rate) or Find my rate from a bill.
- Enter the market value — the property's fair sale price, not the assessed value from the tax bill.
- Enter the assessment ratio as a percent from your county assessor's notice; if the notice shows only an assessed value, divide it by the market value. Use 100% if you do not know.
- If you have a homestead or other exemption, pick the type (dollar amount or percent of assessed value) and enter it.
- In Calculate my tax, enter the tax rate exactly as your bill states it and pick the notation (%, mills, $ per $100 or $ per $1,000); read the annual tax, the monthly escrow figure and the rate in all four notations.
- In Find my rate, enter your annual bill; the calculator works back to the effective rate on taxable value and on market value.
Worked examples
$350,000 home, 100% assessment, 1.2% effective rate (the page defaults)
Assessed value: $350,000 × 100% = $350,000.No exemption: taxable value = $350,000.Annual tax: $350,000 × 0.012 = $4,200.Monthly (escrow): $4,200 ÷ 12 = $350.00.Effective rate on market value: $4,200 ÷ $350,000 = 1.2000%.Same rate in mills: 1.2% × 10 = 12.000 mills.Same rate per $100: $1.200; per $1,000: $12.000.
Annual tax $4,200.00 · monthly $350.00 · effective on market 1.2000%
$450,000 home, 80% assessment, $50,000 homestead exemption, 15 mills (choose "Dollar amount" and "Mills")
Assessed value: $450,000 × 80% = $360,000.Exemption: $50,000 (dollar homestead).Taxable value: $360,000 − $50,000 = $310,000.Rate: 15 mills = 15 / 1,000 = 1.5% effective.Annual tax: $310,000 × 0.015 = $4,650.00.Monthly: $4,650.00 ÷ 12 = $387.50.Effective rate on market: $4,650 ÷ $450,000 = 1.0333%.
Annual tax $4,650.00 · monthly $387.50 · effective on market 1.0333%
Find my rate: $3,500 annual bill on a $280,000 home, 100% assessment
Market value: $280,000. Assessment ratio: 100%. Taxable value: $280,000.Effective rate: $3,500 ÷ $280,000 = 0.012500 = 1.2500%.In mills: 0.012500 × 1,000 = 12.500 mills.Per $100: $1.250. Per $1,000: $12.500.Effective rate on market value: $3,500 ÷ $280,000 = 1.2500%.
Effective rate 1.2500% = 12.500 mills = $1.250 per $100 = $12.500 per $1,000
Methodology
How property tax is actually calculated
The rate on your bill is almost never a percentage of market value. It applies to your assessed value — sometimes a fraction of what you paid — after any exemptions come off first, so the same 15-mill rate can mean 1.5% of one home's value and barely 1% of another's.
Read sources and limitsWhat a property tax calculator works out
A property tax calculator turns three figures from your assessment notice into an annual tax: the market value, the assessment ratio that converts it to an assessed value, and the rate the taxing authorities apply after exemptions come off. It returns the annual bill, the monthly escrow figure, the effective rate on market value and the rate in every common notation.
At the page defaults — a $350,000 home assessed at 100% with no exemption and a 1.2% rate — the annual tax is $4,200.00 and the escrow figure $350.00 a month. The same inputs read as 12 mills, $1.20 per $100 or $12.00 per $1,000 give the same $4,200, which is the point of the notation converter beside the result.
Assessed value vs market value: why the ratio matters
Market value is what your property would sell for between a willing buyer and seller — roughly what you paid, or what an appraiser would estimate today. Assessed value is the number your county assessor assigns for tax purposes, and it is often a fraction of market value. The fraction is the assessment ratio (also called the equalization ratio or level of assessment), and it varies enormously: some jurisdictions assess at 100% of market value, others at 80%, 70% or as low as 10% for certain property classes.
This matters because the property tax rate on your bill is applied to the assessed value, not to market value. If your home is worth $400,000 but the county assesses at 80%, the assessed value is $320,000 — and that is the base the rate is multiplied against. A rate of 1.5% against $320,000 produces a $4,800 tax, not 1.5% of $400,000 ($6,000). The effective rate on your market value is only 1.2%, not 1.5%.
To find your assessment ratio, look at your most recent assessment notice. It will state both the assessed value and — in many counties — the market value or "appraised value" the assessor used. Dividing assessed by market gives you the ratio. If your county uses full market-value assessment, the ratio is 100%.
Millage rate calculator: mills, percent, per $100 and per $1,000
Different jurisdictions express their tax rate in different notations, all of which mean the same thing. An effective rate of 1.2% is also 12 mills, $1.20 per $100 of assessed value, or $12.00 per $1,000 of assessed value — four ways to write the identical number. The word "millage" comes from the Latin for thousand: one mill is one thousandth (0.001), so a 12-mill rate is 0.012, or 1.2%.
The per-$100 and per-$1,000 notations are common on local government tax notices and in property-tax surveys. If your county's published rate is "$13.27 per $1,000" and you see "$13.27" on the notice, you are looking at a per-$1,000 rate — not a percentage. Entering it as a percentage would give you a tax ten times too large. This calculator lets you choose the notation so you can enter the number exactly as it appears on your bill; it converts to all four representations in the result strip.
To find your rate, check your most recent property tax bill, your county assessor's website, or the county auditor's rate schedule. Rates are set annually by the taxing authorities (county, city, school district, special districts) and applied to the assessed value determined by the assessor. The two functions are separate in most states.
Exemptions: homestead, senior, veteran and others
Most jurisdictions offer exemptions that reduce the taxable value — the base the rate is applied to — not the assessed value or the market value. The most common is the homestead exemption, available to owner-occupants of primary residences. It can be a fixed dollar amount (e.g., "the first $50,000 of assessed value is exempt") or a percentage of assessed value (e.g., "25% of assessed value is exempt for homeowners").
Other common exemptions include a senior citizens' freeze (which caps the assessed value for qualifying elderly homeowners), a veterans' or disabled-veterans' exemption, an agricultural exemption, and energy-efficiency or solar exemptions. Each jurisdiction sets its own eligibility rules and amounts. Check your county assessor's or property appraiser's website for the exemptions available to you — many are not applied automatically and must be filed for.
This calculator models a single exemption (dollar or percent) applied against assessed value. If you have multiple stacked exemptions, add them together as a dollar total and enter that as the dollar exemption type. The result shows the exemption separately in the breakdown so you can verify the arithmetic.
How much is property tax? The effective rate versus the stated rate
The effective rate on market value — annual tax divided by market value — is the number that makes cross-jurisdiction comparisons meaningful. Two neighbours with identical homes may have very different bills if one county assesses at 60% and the other at 100%, even if their published millage rates are identical.
This is why the state "average" rates published by tax-research organisations are medians of effective rates across counties, not stated millage rates — and why they are not your rate. The U.S. Census Bureau's American Community Survey publishes median real estate taxes paid by county, which researchers convert to effective rates. A state figure of "1.1%" is a median across every county in the state and may have almost nothing to do with the taxing district you live in. Your county assessor's rate schedule is the only authoritative source for your rate; the sensitivity chart below shows your bill at reference rates from 0.5% to 2.5% so you can see where it sits.
The effective rate on market value also changes if your assessed value is not updated to reflect current market conditions. In many states assessments lag market prices or are capped year to year — a home assessed at a value from two years ago may have a higher effective rate if prices have fallen, or a lower one if they have risen. This calculator computes the effective rate from what you enter; if the assessed value on your notice is stale, enter the current market value and the current assessed value and let the ratio carry the difference.
Property tax calculator by address or by state: what this page cannot do
"By address" lookups: this calculator cannot look up your property's assessed value, your jurisdiction's rate, or your exemption status by address. Every number is one you enter. To find your rate by address, go to your county assessor's or tax collector's website and search for your parcel — assessors publish this information. If you are not sure which county assessor covers your property, search for "[your county name] assessor's office" or "[your county name] property tax".
"By state": there is no state property tax rate to apply. Rates are set by counties, cities, school districts and special districts, so a state figure can only be a median. This site shows no state averages because it has no dataset citing Census ACS for them; the chart uses round reference rates instead.
Special assessments and fees: most property tax bills include line items beyond the general levy — improvement districts, Mello-Roos (in California), stormwater fees, fire protection districts and similar. This calculator models only the base levy from rate × taxable value. SALT deductibility: the federal deduction for state and local taxes, including real property taxes, is limited per household under IRC §164(b)(6); see IRS Publication 530 and Topic 503. This calculator does not compute that deduction.
Property Tax questions
How is property tax calculated?
Annual property tax = taxable value × rate. The county assessor sets the assessed value (market value × the assessment ratio), exemptions come off to give the taxable value, and the taxing authorities' combined rate — stated as a percent, mills, or dollars per $100 or $1,000 — is applied to it. A $350,000 home assessed at 100% with a 1.2% rate owes $4,200 a year, $350 a month through a mortgage escrow.
What is a mill rate (millage rate)?
A mill is one thousandth (0.001), so 12 mills means $12 of tax per $1,000 of taxable value — the same as a 1.2% effective rate or $1.20 per $100. Counties, cities, school districts and special districts each levy their own millage and the bill adds them together. Divide the total mills by 1,000 to get the decimal rate, or by 10 to get the percentage.
What is the difference between assessed value and market value?
Market value is what the property would sell for; assessed value is the figure the county assigns for tax, often a fraction of market value set by the assessment ratio. A county that assesses at 80% taxes $320,000 of a $400,000 home, so a 1.5% stated rate is only 1.2% of market value. Most assessment notices show both figures.
How do I find my property's assessment ratio?
Divide the assessed value on your assessment notice by the market (or "appraised") value it shows; the result is the ratio. If the notice shows only one figure, your county assessor's website lists the level of assessment for each property class, and some states fix it by law — Florida assesses residential property at 100% of just value, for example. Use 100% if you cannot find it.
How much is property tax on a $300,000 house?
$3,600 a year at a 1.2% effective rate with 100% assessment and no exemption — $300 a month. At 0.5% it is $1,500; at 2.0% it is $6,000. The rate depends entirely on your county, city and school district, not your state, so enter the rate from your own bill. The chart below the result shows the same home at reference rates from 0.5% to 2.5%.
Can I look up my property tax by address?
Not here — this calculator looks nothing up; every number is one you enter. Your county assessor's or property appraiser's website has a parcel search by address that shows your assessed value, exemptions, taxing districts and each district's rate, and the tax collector's site shows the bill. Search for "[county name] assessor" or "[county name] property tax parcel search".
Is property tax deductible on my federal tax return?
Real property taxes are deductible as state and local taxes (SALT) if you itemize, subject to the SALT cap in IRC §164(b)(6) for the year, and only to the extent your itemized deductions exceed the standard deduction. The cap covers property taxes plus state and local income or sales taxes together. See IRS Publication 530 and Topic 503; this calculator does not compute the deduction.
Why is my effective rate lower than the rate on my bill?
Because the stated rate applies to assessed value after exemptions, not to market value. At an 80% assessment ratio a 1.5% stated rate is 1.2% of market value (0.015 × 0.80), and a $50,000 homestead exemption on a $300,000 assessed value applies the rate to only $250,000, lowering it further. The effective rate on market value is the figure that compares fairly across jurisdictions.
How do I calculate property tax from the mill rate?
Multiply the taxable value by the mills and divide by 1,000. A $310,000 taxable value at 15 mills is $310,000 × 15 ÷ 1,000 = $4,650 a year. Choose "Mills" as the rate notation on this page and enter the figure exactly as your bill prints it; the result strip shows the same rate as a percent (1.5%), per $100 ($1.50) and per $1,000 ($15.00).
Is property tax based on the purchase price or the assessed value?
On the assessed value, which the assessor sets — often from the purchase price after a sale and then adjusted, capped or reassessed on a schedule that varies by state. The rate applies to the assessed value less exemptions, never directly to the price. Enter the current market value and your assessment ratio here; if your notice shows the assessed value, divide it by the market value to get the ratio.
Source notes
Method, sources & limitations
Every figure on this page comes from the formula above applied to the values you enter. Nothing is estimated from market data, and no result is a forecast. These are the sources behind the method and any fixed figures it uses:
- Texas Comptroller — Property Tax Basics (appraised value, exemptions, rates)
- IRS Publication 530 — Tax Information for Homeowners (real property taxes and SALT)
- IRS Topic 503 — Deductible taxes
- U.S. Census Bureau ACS Table B25103 — Median Real Estate Taxes Paid (context only)
- International Association of Assessing Officers (IAAO) — Glossary of Assessment and Property Appraisal Terminology
Educational information only. Results are estimates produced from the assumptions you enter, and are not financial, tax, legal or medical advice. Check anything that matters against a qualified professional and the cited sources.