About Home Values
A free tool for Harris County homeowners to find comparable properties and build evidence for a property tax protest.
What it does
Search HCAD Records
Look up any Harris County property by owner name, street address, street name, or ZIP code. Data is sourced directly from the Harris County Appraisal District.
Find Comparable Properties
A multi-factor similarity algorithm ranks nearby properties by how closely they match yours in living area, lot size, bed/bath count, quality, condition, age, building type, features, stories, and distance.
Get a Protest Recommendation
Your price per square foot is compared against the median of your comparables. If you are assessed significantly higher, the tool recommends protesting and explains why.
Export Evidence
Download your evidence report as PDF or export the comparable table to CSV, including match scores and score breakdowns.
How it works
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1
Search for your property
Enter your last name, address, street, or ZIP on the home page. Results show assessed value, building area, lot size, and price per square foot (PPSF).
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2
Open the similar properties view
Click "Find Similar" next to your property. The algorithm searches within the selected radius for properties that match yours across 11 weighted factors.
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3
Review your comparables
Properties are ranked by match score (0–100 with one decimal). Score Details shows how each factor contributed, so a 91.4 match can be distinguished from an 87.2 or 96.8 match.
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4
See your protest recommendation
If at least 3 comparables exist, the tool compares your PPSF to the median. Being 20% or more above the median triggers a Recommend Protesting result; 10–19% above triggers Consider Protesting.
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5
Export your evidence
Use the Evidence Report, PDF export, or CSV export to download your comparable list and score details. Bring it to your HCAD protest hearing as supporting evidence for an unequal appraisal argument.
Example walkthrough
Jane Smith owns a 3-bedroom, 2-bathroom home at 1234 Oak St, Houston, TX 77008, built in 1985 with a quality grade of C. HCAD assessed it at $420,000 (2,100 sqft heated area = $200/sqft).
She searches her last name and ZIP on the home page and finds her property in the results.
She clicks Find Similar. The tool returns 18 comparable homes with an average match score of 74 — all within a few miles, with similar square footage, age, and bedroom/bathroom counts.
The median PPSF of those 18 comparables is $162/sqft. Jane's PPSF of $200 is 23% above the median.
Recommend Protesting
Your price per sqft ($200.00) is about 23% above the median ($162.00) of 18 similar properties (avg match score 74).
Jane exports the comparable list to CSV and uses it as evidence at her HCAD protest hearing, arguing unequal appraisal.
How the similarity score works
Each candidate property is scored 0–100 across up to 11 factors. Scores are shown with one decimal place, and each comparable includes Score Details so you can see which physical traits helped or hurt the match. Missing data reduces the available weight pool, then the score is multiplied by a completeness factor (0.80–1.00).
| Factor | Max Points | How it is measured |
|---|---|---|
| Heated / Living Area | 24 | % size difference: exact → full credit, ±5% → strong credit, ±20% → moderate credit, ±50% → minimal credit, >75% → 0 |
| Bedrooms | 14 | Count difference: exact → full credit, ±1 bed → partial credit, ±2 beds → low credit, ±4+ → 0 |
| Bathrooms | 12 | Count difference: exact → full credit, ±0.5 bath → strong partial credit, ±1.0 bath → low partial credit, ±2.5+ → 0 |
| Land / Lot Size | 10 | % lot size difference: exact → full credit, ±5% → strong credit, ±20% → moderate credit, ±50% → low credit, >80% → 0 |
| Quality Grade | 10 | HCAD rank gap (X=7, A=6, B=5, C=4, D=3, E=2, F=1): 0 ranks apart → 1.0, 1 rank → 0.72, 3 ranks → 0.18, 5+ → 0 |
| Age (Year Built) | 8 | Effective-year difference: exact → full credit, ±5 yrs → strong partial credit, ±10 yrs → moderate credit, ±25 yrs → low credit, 40+ yrs → 0 |
| Condition Code | 6 | Same rank system as quality grade |
| Building Character | 4 | Building style, type, and class: exact match → 1.0, partial → 0.4–0.65, no match → 0 |
| Extra Features | 4 | Jaccard similarity of feature codes (pool, garage, patio, spa, sprinklers, etc.): intersection ÷ union |
| Stories | 4 | Story difference: 0 → 1.0, ±0.5 → 0.70, ±1.0 → 0.35, 2.0+ → 0 |
| Distance | 4 | Distance relative to search radius: same location → full credit, 10% of radius → high credit, 50% → moderate credit, full radius → minimal credit |
| Total | 100 | Score = (weighted similarity points ÷ available weight) × completeness (0.80–1.00) × 100. High-90s now require nearly identical attributes, not just broadly similar homes. |
Score labels
84.0–100
Best Match
70.0–83.9
Highly Similar
52.0–69.9
Good Match
36.0–51.9
OK Match
0–35.9
Broad Match
Data source
Harris County Appraisal District (HCAD)
All property records are sourced from HCAD's publicly available data files, updated periodically. The raw files are free to download at:
https://download.hcad.org/data/Files used: Real_acct_owner.txt (property & owner records), Real_building_land.zip (building details & extra features), Parcels.zip (GIS coordinates)