Loan to Value (LTV) Ratio Calculator
This calculator computes Loan-to-Value (LTV) as a straightforward ratio between loan amounts and property value. It shows both the primary LTV (single loan) and combined LTV (CLTV) when you include additional loans such as a second mortgage or HELOC.
Use the Target LTV field to estimate the maximum primary loan you could take while remaining at or below a specified LTV after accounting for existing secondary debt. Results are approximate and intended for planning and comparison; final underwriting may apply appraisal adjustments, seasoning rules, or different definitions of value.
Governance
Record 9a9db93bf09d • Reviewed by Fidamen Standards Committee
Inputs
Results
Primary LTV (%)
8000.00%
Combined LTV (CLTV %) — includes additional loans
8000.00%
Primary LTV (decimal)
0.8
Combined LTV (decimal)
0.8
Down payment implied by primary loan
$50,000.00
Down payment implied by combined loans
$50,000.00
Maximum primary loan for target LTV (after other loans)
$200,000.00
| Output | Value | Unit |
|---|---|---|
| Primary LTV (%) | 8000.00% | % |
| Combined LTV (CLTV %) — includes additional loans | 8000.00% | % |
| Primary LTV (decimal) | 0.8 | — |
| Combined LTV (decimal) | 0.8 | — |
| Down payment implied by primary loan | $50,000.00 | USD |
| Down payment implied by combined loans | $50,000.00 | USD |
| Maximum primary loan for target LTV (after other loans) | $200,000.00 | USD |
Visualization
Methodology
The tool applies direct arithmetic formulas: divide the relevant loan sum by the property value. Combined LTV adds other outstanding loans to the primary loan before dividing by value.
Validation and development practices follow recognized software quality and assurance principles. Recommended governance and testing reference ISO quality management guidance and IEEE software validation recommendations. For data handling and operational security, follow NIST and ISO/IEC information security guidance.
Worked examples
Example 1: Primary loan $200,000 on a $250,000 property → Primary LTV = (200000 / 250000) × 100 = 80%.
Example 2: Same primary loan plus $20,000 HELOC → Combined LTV = ((200000 + 20000) / 250000) × 100 = 88%.
F.A.Q.
Does this calculator replace lender underwriting?
No. This tool provides an arithmetic estimate. Lenders may apply appraised value adjustments, repair cost deductions, seasoning requirements, or different definitions for included debt. Always confirm with your lender or servicer.
Which loans should I include as 'other loans'?
Include outstanding second mortgages, home equity lines of credit (HELOCs), and any junior liens that the lender considers in combined LTV calculations. Do not include consumer unsecured debt.
Why might my calculated LTV differ from a lender's LTV?
Differences arise from appraisal methods (market value vs. purchase price), effective dates, rounding rules, and whether the lender includes certain fees or credits in the loan amount. This calculator uses raw amounts you enter without lender-specific adjustments.
How accurate is the result and what safeguards exist?
Results are mathematically exact given your inputs but are subject to input errors, rounding, and lender policy variation. Development and validation reference IEEE and ISO practices; operational security and identity guidance reference NIST standards. This is not a substitute for professional appraisal or lender confirmation.
Sources & citations
- NIST — Frameworks and guidance for secure, reliable systems — https://www.nist.gov
- ISO — Quality management and information security standards (ISO 9001, ISO/IEC 27001) — https://www.iso.org
- IEEE — Software engineering and verification standards — https://standards.ieee.org
- OSHA — General guidance on risk management and operational safety — https://www.osha.gov
- HUD — FHA Single Family Housing Policy Handbook 4000.1 — https://www.hud.gov/program_offices/housing/sfh/handbook_4000-1
- HUD — Property Valuation and Appraisals (HUD 4155.2) — https://www.hud.gov/sites/documents/4155-2_4.pdf
- Fannie Mae — Selling Guide — https://selling-guide.fanniemae.com/
Further resources
Versioning & Change Control
Audit record (versions, QA runs, reviewer sign-off, and evidence).
Record ID: 9a9db93bf09dWhat changed (latest)
v1.0.0 • 2025-11-21 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Public QA status
PASS — golden 25 + edge 120
Last run: 2026-01-23 • Run: golden-edge-2026-01-23
Versioning & Change Control
Audit record (versions, QA runs, reviewer sign-off, and evidence).
What changed (latest)
v1.0.0 • 2025-11-21 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Public QA status
PASS — golden 25 + edge 120
Last run: 2026-01-23 • Run: golden-edge-2026-01-23
Engine
v1.0.0
Data
Baseline (no external datasets)
Content
v1.0.0
UI
v1.0.0
Governance
Last updated: Nov 21, 2025
Reviewed by: Fidamen Standards Committee (Review board)
Credentials: Internal QA
Risk level: low
Reviewer profile (entity)
Fidamen Standards Committee
Review board
Internal QA
Entity ID: https://fidamen.com/reviewers/fidamen-standards-committee#person
Semantic versioning
- MAJOR: Calculation outputs can change for the same inputs (formula, rounding policy, assumptions).
- MINOR: New features or fields that do not change existing outputs for the same inputs.
- PATCH: Bug fixes, copy edits, or accessibility changes that do not change intended outputs except for previously incorrect cases.
Review protocol
- Verify formulas and unit definitions against primary standards or datasets.
- Run golden-case regression suite and edge-case suite.
- Record reviewer sign-off with credentials and scope.
- Document assumptions, limitations, and jurisdiction applicability.
Assumptions & limitations
- Uses exact unit definitions from the Fidamen conversion library.
- Internal calculations use double precision; display rounding follows the unit's configured decimal places.
- Not a substitute for calibrated instruments in regulated contexts.
- Jurisdiction-specific rules may require official guidance.
Change log
v1.0.0 • 2025-11-21 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Areas: engine, content, ui • Reviewer: Fidamen Standards Committee • Entry ID: 5d3cb60a9115