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POWERED BY PropTechUSA.ai ESTIMATE ENGINE v1 · 4 SOURCES · ALL 50 STATES
4 Sources · Full Transparency · Free Tier

The rent estimate API
that shows its work.

Every other API gives you a number and tells you to trust it. PropData shows you exactly which sources contributed, what weight each got, and how confident the model is. You own the logic. You can defend every number.

Get free API key → See the model ↓
SAMPLE RESPONSE — /v1/estimate?zip=55104&beds=2
RENT ESTIMATE — 55104, MN 2 BEDROOM
LOW
$1,482
MID ★
$1,609
HIGH
$1,738
Confidence: 100% Trend: Stable YoY: +3.63% Range: ±8%
MODEL WEIGHTS — HOW WE GOT $1,609
Zillow ZORI
40% $1,534
Census ACS
25% $1,159
HUD FMR
20% $1,685
Redfin Cap Rate
15% $1,736
The Estimate Engine

Four sources. Explicit weights.
Full transparency.

Most rent estimate APIs are black boxes. They give you a number, maybe a range, and no explanation. PropData's estimate engine is a documented weighted model. Every source, every weight, every calculation is returned in the API response so you can audit, explain, and trust the output.

40%
SOURCE 1 — ZILLOW ZORI
Median Asking Rent

The Zillow Observed Rent Index tracks median asking rents for active listings. It's the strongest single signal for what you can actually charge today — not what renters paid last year.

Highest weight — reflects current market pricing, not historical actuals.
25%
SOURCE 2 — US CENSUS ACS
Median Gross Rent

Census ACS 5-year estimates capture what renters are actually paying across all occupied units — not just newly listed ones. It anchors the estimate to real affordability in the market.

Anchors against asking-rent inflation. Reflects what renters can actually pay.
20%
SOURCE 3 — HUD FAIR MARKET RENTS
Bedroom-Level Benchmark

HUD publishes annual Fair Market Rents for every US county by bedroom count. These are the government's benchmark for reasonable rent — and the basis for Section 8 voucher amounts.

Government-grade bedroom-specific benchmark. Used directly for the right bed count.
15%
SOURCE 4 — REDFIN CAP RATE MODEL
Implied Market Rent

Using Redfin median sale prices with a 6.5% cap rate assumption, we derive what a rational investor would need to charge to generate market-rate returns. A market sanity check.

Investment-grade cross-check. Prevents estimates that no investor would underwrite.

You can't sell a number
you can't explain.

If you're building a tool that suggests a rent price to a landlord, a comp to an investor, or a valuation to a buyer — they're going to ask "why?" PropData is the only rent estimate API where you have an actual answer.

🏠
Landlords trust it

Show the breakdown: "Our estimate uses Zillow market data, government benchmarks, and census actuals. Here's how each one contributed." That's a conversation starter, not a black box.

📊
Investors underwrite it

Institutional investors don't accept a single number. They want a range and a basis. PropData returns low/mid/high with confidence scores — underwriting-ready out of the box.

⚖️
Lawyers can defend it

Fair housing compliance, Section 8 disputes, rent control challenges — the methodology is documented, government-sourced, and auditable. Not a proprietary algorithm you can't explain.

Integration

One endpoint. Every bedroom.
All 50 states.

Pass ?beds=0 through ?beds=4 for bedroom-specific estimates. The model applies nationally-calibrated multipliers derived from HUD FMR ratios.

GET /v1/estimate?zip=55104&beds=2
// Full response with model transparency
{
  "estimate": {
    "bedrooms": 2,
    "monthly_low": 1482,   // -8% from mid
    "monthly_mid": 1609,   // weighted average
    "monthly_high": 1738,  // +8% from mid
    "confidence_pct": 100// all 4 sources returned data
    "market_trend": "stable",
    "yoy_rent_change": "+3.63%"
  },
  "methodology": {
    "data_points": [
      { "source": "Zillow ZORI", "weight_pct": 40, "adjusted_rent": 1534 },
      { "source": "Census ACS",  "weight_pct": 25, "adjusted_rent": 1159 },
      { "source": "HUD FMR",    "weight_pct": 20, "adjusted_rent": 1685 },
      { "source": "Redfin",     "weight_pct": 15, "adjusted_rent": 1736 }
    ]
  }
}

What you get vs
every other option.

PROPDATA ESTIMATE ENGINE
Low / mid / high range
Confidence score (0–100%)
Full model weights returned in API
4 named sources, individually auditable
Bedroom-specific (Studio → 4BR)
Government-sourced data (HUD + Census)
Market trend + YoY change
Free tier. $49/mo flat. No per-call fees.
TYPICAL ESTIMATE API
Single point estimate
No confidence score
Black box — methodology not disclosed
Sources not named
Varies
Proprietary model only
Sometimes
Per-call billing
What Developers Build

Built for real use cases,
not demos.

Rental Pricing Tools

Give landlords a defensible asking price with a low/mid/high range they can explain to their property manager. No more guessing from Zillow comps.

/v1/estimate?zip=ZIP&beds=BR

AI Real Estate Agents

Feed structured rent estimates directly to your LLM. The JSON response is clean, labeled, and includes the reasoning — perfect for RAG and AI tools.

JSON → LLM context → answer

Section 8 Compliance Tools

HUD FMR is one of the four model sources. For tools that need to show government-aligned rent benchmarks by bedroom, PropData is the only API that surfaces this via simple REST call.

HUD FMR included in model weights

Investment Underwriting

Low/mid/high rent scenarios with confidence scores are exactly what investment models need. Pair with cap rate assumptions to get NOI range for any property address.

monthly_low/mid/high × 12 = NOI range

Portfolio Management Apps

Batch all your ZIP codes through /v1/estimate to build a rent roll projection. State-level queries let you benchmark portfolios across markets.

/v1/estimate?state=TX&beds=2

Tenant-Facing Tools

Show renters what "fair market" means in their neighborhood. The HUD FMR data gives you government-sanctioned benchmarks — credible, explainable, defensible.

fmr_2br — government benchmark

Start estimating rents today.

Free tier includes 50 requests/hour — enough to explore any market. Upgrade to Pro for 500/hour at flat $49/mo.

FREE TIER
$0
forever · no credit card
50 requests/hour
All endpoints including estimate
Full model transparency
All 5 bedroom types
PRO
$49
/month · flat · no per-call fees
500 requests/hour
All 9 data sources
Priority support
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