US Mortgage Calculator
REMOTE · WWW.USMORTGAGECALC.COM · SCANNED SEP 20
US mortgage calculator and amortization API with 50-state property tax, PMI, and affordability data.
Available components
How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score → Why this is hard to score →
Endpoint Security80
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- No authorisation is required to call this server. Every tool declares its destructiveHint and none is destructive, so open access doesn't expose one. See how to fix → View diagnostics → Partial
- HTTPS is enforced; there's no plaintext access path. View diagnostics → Pass
- The HSTS (Strict-Transport-Security) header is present. View diagnostics → Pass
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability80
- 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).Pass
- AI-judged instruction clarity (excellent).Pass
- Context-footprint check failed: tool/resource definitions use about 3008 tokens (~176/item across 17 items; 11 tools + 6 resources), over budget; trim descriptions and params. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management100
- No destabilizing schema changes in the last 30 days.Pass
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 11 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 13 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a current MCP spec version (2026-07-28).Pass
How do I install the US Mortgage Calculator MCP server?
US Mortgage Calculator is a hosted endpoint at https://www.usmortgagecalc.com/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
remote · www.usmortgagecalc.com
claude mcp add --transport http com-usmortgagecalc-mortgage 'https://www.usmortgagecalc.com/mcp'
{
"mcpServers": {
"com-usmortgagecalc-mortgage": {
"url": "https://www.usmortgagecalc.com/mcp"
}
}
} {
"servers": {
"com-usmortgagecalc-mortgage": {
"type": "http",
"url": "https://www.usmortgagecalc.com/mcp"
}
}
} [mcp_servers.com-usmortgagecalc-mortgage] url = "https://www.usmortgagecalc.com/mcp"
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"com-usmortgagecalc-mortgage": {
"type": "remote",
"url": "https://www.usmortgagecalc.com/mcp",
"enabled": true
}
}
} openclaw mcp add com-usmortgagecalc-mortgage --url 'https://www.usmortgagecalc.com/mcp' --transport streamable-http
mcp_servers:
com-usmortgagecalc-mortgage:
url: "https://www.usmortgagecalc.com/mcp" {
"McpServers": {
"com-usmortgagecalc-mortgage": {
"Transport": "http",
"Url": "https://www.usmortgagecalc.com/mcp"
}
}
} assistant mcp add com-usmortgagecalc-mortgage -t streamable-http -u 'https://www.usmortgagecalc.com/mcp'
{
"mcpServers": {
"com-usmortgagecalc-mortgage": {
"type": "http",
"url": "https://www.usmortgagecalc.com/mcp"
}
}
} The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.
Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 13 Sept 26 0
- Stability: 0.97 → pass security
- 12 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 93 to 97. That category is still filling its 30-day observation window: 28 days of observed history at the previous scan, 29 at this one. The score rises as the window fills, whether or not the server changes.
- 9 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 83 to 87. That category is still filling its 30-day observation window: 25 days of observed history at the previous scan, 26 at this one. The score rises as the window fills, whether or not the server changes.
- 7 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 77 to 80. That category is still filling its 30-day observation window: 23 days of observed history at the previous scan, 24 at this one. The score rises as the window fills, whether or not the server changes.
- 5 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 70 to 73. That category is still filling its 30-day observation window: 21 days of observed history at the previous scan, 22 at this one. The score rises as the window fills, whether or not the server changes.
- 3 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 63 to 67. That category is still filling its 30-day observation window: 19 days of observed history at the previous scan, 20 at this one. The score rises as the window fills, whether or not the server changes.
- 1 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 57 to 60. That category is still filling its 30-day observation window: 17 days of observed history at the previous scan, 18 at this one. The score rises as the window fills, whether or not the server changes.
- 30 Aug 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 50 to 53. That category is still filling its 30-day observation window: 15 days of observed history at the previous scan, 16 at this one. The score rises as the window fills, whether or not the server changes.
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 20 Sept 2026 · Probed https://www.usmortgagecalc.com/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=www.usmortgagecalc.com | CN=YR1,O=Let's Encrypt,C=US | 10 Aug 2026 | 8 Nov 2026 | RSA 2048 | SHA256-RSA | 5100ccd5667fd45e393118159068ffbdde3 |
| SANs: www.usmortgagecalc.com | ||||||
| CN=YR1,O=Let's Encrypt,C=US (CA) | CN=Root YR,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | RSA 2048 | SHA256-RSA | a20253f15f2691c05dc1ce13b9bcca4e |
| CN=Root YR,O=ISRG,C=US (CA) | CN=ISRG Root X1,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | RSA 4096 | SHA256-RSA | f24b6d17f9d9ad7cb1c9fea78782699f |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of www.usmortgagecalc.com. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| com. | present | 19718 | 13 | Verified |
| usmortgagecalc.com. | absent | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication No authorisation required
The endpoint answered without asking for a token. Anyone who knows the URL can reach it.
| Result | No authorisation required |
|---|---|
| HTTP status | 200 |
| Header | Value |
|---|---|
| strict-transport-security | max-age=63072000 |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://www.usmortgagecalc.com/mcp | Verified | 200 | |
| http (plaintext) | http://www.usmortgagecalc.com/mcp | HTTPS enforced | 308 | https://www.usmortgagecalc.com/mcp |
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
calculate_affordability Work out how much house someone can afford ~355
Maximum affordable home price from income, existing debt payments and available down payment, using the 28/36 qualifying ratios. Reports which of the two ratios is the binding constraint, which is the actionable part: a buyer limited by the back-end ratio can raise their budget by clearing debt, one limited by the front-end ratio cannot.
| Name | Type | Req | Description |
|---|---|---|---|
| annualGrossIncome | number | yes | Household income before tax, in US dollars per year. |
| annualInsurance | number | – | Annual homeowners insurance premium. |
| annualInterestRatePercent | number | – | Annual nominal interest rate as a percentage, for example 6.5 for 6.5%. |
| backEndRatioPercent | number | – | Maximum total debt as a share of gross income. 36 is conservative; lenders often allow 45 and sometimes 50. |
| downPaymentAmount | number | yes | Cash available for the down payment, in US dollars. A dollar amount, not a percentage. |
| frontEndRatioPercent | number | – | Maximum housing cost as a share of gross income. 28 is the conservative standard. |
| loanTermYears | integer | – | Loan term in years. Most US mortgages are 15 or 30. |
| monthlyDebtPayments | number | – | Existing minimum monthly debt payments: car loans, student loans, credit card minimums. Excludes housing. |
| monthlyHoa | number | – | Monthly HOA dues. |
| propertyTaxRatePercent | number | – | Annual property tax as a percentage of home value. Omit and pass `state` instead to use that state's average. |
| state | string | – | Full US state name, for example "Texas". Used to look up the average property tax rate. Either this or propertyTaxRatePercent is required. |
No output schema declared.
No examples provided.
calculate_amortization Build an amortization schedule ~335
Payment-by-payment breakdown of how a loan is repaid, showing the split between principal and interest and the falling balance. Use granularity 'monthly' for the first years in detail, 'yearly' for a whole-term overview. Also reports how much sooner extra principal pays the loan off.
| Name | Type | Req | Description |
|---|---|---|---|
| annualInsurance | number | – | Annual homeowners insurance premium in US dollars. |
| annualInterestRatePercent | number | – | Annual nominal interest rate as a percentage, for example 6.5 for 6.5%. |
| downPaymentPercent | number | – | Down payment as a percentage of the purchase price, 0 to 100. Not a dollar amount. |
| granularity | string | – | Yearly returns one row per year; monthly returns one row per payment, up to 600 rows. |
| homePrice | number | yes | Purchase price of the home in US dollars. |
| loanTermYears | integer | – | Loan term in years. Most US mortgages are 15 or 30. |
| loanType | string | – | Loan programme. Affects mortgage insurance and upfront fees. |
| monthlyExtraPrincipal | number | – | Additional principal paid each month. Shortens the loan rather than lowering the payment. |
| monthlyHoa | number | – | Monthly homeowners association dues in US dollars. |
| propertyTaxRatePercent | number | – | Annual property tax as a percentage of home value. Omit and pass `state` instead to use that state's average. |
| state | string | – | Full US state name, for example "Texas". Used to look up the average property tax rate. Either this or propertyTaxRatePercent is required. |
No output schema declared.
No examples provided.
calculate_mortgage Calculate a monthly mortgage payment ~313
Full monthly housing cost for a US mortgage: principal and interest, property tax, homeowners insurance, mortgage insurance and HOA dues, plus lifetime totals and payoff timing. Pass a state name to use that state's average property tax rate. This is the right tool for 'what would my payment be on a $400,000 house'.
| Name | Type | Req | Description |
|---|---|---|---|
| annualInsurance | number | – | Annual homeowners insurance premium in US dollars. |
| annualInterestRatePercent | number | – | Annual nominal interest rate as a percentage, for example 6.5 for 6.5%. |
| downPaymentPercent | number | – | Down payment as a percentage of the purchase price, 0 to 100. Not a dollar amount. |
| homePrice | number | yes | Purchase price of the home in US dollars. |
| loanTermYears | integer | – | Loan term in years. Most US mortgages are 15 or 30. |
| loanType | string | – | Loan programme. Affects mortgage insurance and upfront fees. |
| monthlyExtraPrincipal | number | – | Additional principal paid each month. Shortens the loan rather than lowering the payment. |
| monthlyHoa | number | – | Monthly homeowners association dues in US dollars. |
| propertyTaxRatePercent | number | – | Annual property tax as a percentage of home value. Omit and pass `state` instead to use that state's average. |
| state | string | – | Full US state name, for example "Texas". Used to look up the average property tax rate. Either this or propertyTaxRatePercent is required. |
No output schema declared.
No examples provided.
calculate_pmi Calculate mortgage insurance ~294
Mortgage insurance for any US loan programme, including the upfront charges most calculators omit. Conventional: monthly PMI and the month it cancels at 80% and 78% loan-to-value. FHA: the 1.75% upfront premium, monthly MIP, and whether it runs for the life of the loan or ends after 11 years. VA: the funding fee, tiered by down payment and prior use, and waivers. USDA: guarantee and annual fees.
| Name | Type | Req | Description |
|---|---|---|---|
| annualInterestRatePercent | number | – | Annual nominal interest rate as a percentage, for example 6.5 for 6.5%. |
| creditScore | integer | – | FHA only: sets the minimum down payment. 580+ qualifies for 3.5%. |
| downPaymentPercent | number | – | Down payment as a percentage of the purchase price, 0 to 100. Not a dollar amount. |
| homePrice | number | yes | Purchase price of the home in US dollars. |
| loanTermYears | integer | – | Loan term in years. Most US mortgages are 15 or 30. |
| loanType | string | – | Loan programme. Affects mortgage insurance and upfront fees. |
| monthlyExtraPrincipal | number | – | Extra principal paid monthly. |
| vaExemptFromFundingFee | boolean | – | VA only: funding fee waived. |
| vaSubsequentUse | boolean | – | VA only: entitlement used before. |
No output schema declared.
No examples provided.
calculate_property_tax Estimate property tax ~96
Annual and monthly property tax for a home, using a state's average effective rate. Also returns how that state ranks nationally and how its rate compares with the national average. For the mechanics behind the number — assessment basis, caps, exemptions, appeal deadlines — use get_state_mortgage_rules.
| Name | Type | Req | Description |
|---|---|---|---|
| homePrice | number | yes | Home value in US dollars. |
| state | string | yes | Full US state name, for example "Texas". |
No output schema declared.
No examples provided.
calculate_refinance Evaluate a refinance ~180
Whether refinancing is worth it: the new payment, monthly saving, and how many months it takes to recover closing costs. Also compares lifetime interest, which catches the common trap where a lower payment costs more overall because the term was reset.
| Name | Type | Req | Description |
|---|---|---|---|
| closingCosts | number | yes | Total cost to close the refinance, in US dollars. |
| currentAnnualRatePercent | number | yes | Interest rate on the existing loan. |
| currentBalance | number | yes | Remaining principal on the existing loan. |
| currentRemainingTermMonths | integer | yes | Months still to run on the existing loan. |
| financeClosingCosts | boolean | – | Roll closing costs into the new balance instead of paying cash. |
| newAnnualRatePercent | number | yes | Interest rate being offered. |
| newTermYears | integer | – | Loan term in years. Most US mortgages are 15 or 30. |
No output schema declared.
No examples provided.
calculate_rent_vs_buy Compare renting with buying ~395
Compares renting and buying on net wealth rather than on monthly payment, accounting for equity, appreciation, maintenance, selling costs, and the return a renter earns on money not spent on a down payment. Returns the year buying overtakes renting. The result is highly sensitive to the appreciation and investment-return assumptions, which are returned alongside it.
| Name | Type | Req | Description |
|---|---|---|---|
| annualHomeAppreciationPercent | number | – | Expected annual home price growth. The answer is highly sensitive to this. |
| annualInsurance | number | – | Annual homeowners insurance premium. |
| annualInterestRatePercent | number | – | Annual nominal interest rate as a percentage, for example 6.5 for 6.5%. |
| annualMaintenancePercent | number | – | Annual upkeep as a percentage of home value. Typically 1 to 2. |
| annualRentIncreasePercent | number | – | Expected annual rent growth. |
| downPaymentPercent | number | – | Down payment as a percentage of the purchase price, 0 to 100. Not a dollar amount. |
| homePrice | number | yes | Purchase price of the home in US dollars. |
| investmentReturnPercent | number | – | Return a renter earns on cash not tied up in a house. |
| loanTermYears | integer | – | Loan term in years. Most US mortgages are 15 or 30. |
| monthlyHoa | number | – | Monthly HOA dues. |
| monthlyRent | number | yes | Current monthly rent for a comparable home. |
| propertyTaxRatePercent | number | – | Annual property tax as a percentage of home value. Omit and pass `state` instead to use that state's average. |
| sellingCostPercent | number | – | Cost of selling, including agent commission. |
| state | string | – | Full US state name, for example "Texas". Used to look up the average property tax rate. Either this or propertyTaxRatePercent is required. |
| yearsToCompare | integer | – | Horizon of the comparison. |
No output schema declared.
No examples provided.
compare_loans Compare loan options side by side ~83
Compares two to five loan scenarios and reports which is cheapest by monthly payment and which by lifetime cost, separately, because they frequently are not the same loan. Use for 15-year versus 30-year, FHA versus conventional, competing lender quotes, or with and without discount points.
| Name | Type | Req | Description |
|---|---|---|---|
| scenarios | array | yes | Two to five loan scenarios to compare side by side. |
No output schema declared.
No examples provided.
estimate_closing_costs Itemise closing costs ~311
Line-by-line buyer closing costs — lender fees, title, appraisal, transfer taxes, prepaid escrow — plus total cash needed at the table including the down payment. Marks which items are worth shopping for and which are fixed by the county, and adds the FHA upfront premium, VA funding fee or USDA guarantee fee where they apply.
| Name | Type | Req | Description |
|---|---|---|---|
| annualInsurance | number | – | Annual homeowners insurance premium. |
| downPaymentPercent | number | – | Down payment as a percentage of the purchase price, 0 to 100. Not a dollar amount. |
| escrowMonths | integer | – | Months of taxes collected up front to open the escrow account. |
| homePrice | number | yes | Purchase price of the home in US dollars. |
| loanType | string | – | Loan programme. Affects mortgage insurance and upfront fees. |
| propertyTaxRatePercent | number | – | Annual property tax as a percentage of home value. Omit and pass `state` instead to use that state's average. |
| state | string | – | Full US state name, for example "Texas". Used to look up the average property tax rate. Either this or propertyTaxRatePercent is required. |
| transferTaxPercent | number | – | State and local transfer tax as a percentage of price. Varies enormously by state. |
| vaExemptFromFundingFee | boolean | – | VA only: exempt from the funding fee, for example a service-connected disability rating. |
| vaSubsequentUse | boolean | – | VA only: entitlement has been used before. |
No output schema declared.
No examples provided.
get_state_mortgage_rules Look up a state's property tax rules ~122
How property tax actually works in one state: how assessed value is derived, any statutory growth cap, the billing cycle, named exemptions such as homestead, the filing deadline, who hears appeals and the window to file, notable county variation, and a link to the state's own tax authority. Use this when the question is about mechanics or deadlines rather than a dollar amount.
| Name | Type | Req | Description |
|---|---|---|---|
| state | string | yes | Full US state name, for example "Texas". Used to look up the average property tax rate. Either this or propertyTaxRatePercent is required. |
No output schema declared.
No examples provided.
list_states List all 50 states with property tax rates ~90
Every US state with its average effective property tax rate, median home value and estimated annual tax. Sortable, so it answers 'which states have the highest property taxes' directly. Call this to discover valid state names for the other tools.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | How many states to return. |
| order | string | – | Sort direction. |
| sortBy | string | – | Ordering of the returned list. |
No output schema declared.
No examples provided.
What is the US Mortgage Calculator MCP server?
US Mortgage Calculator is an MCP server listed in the public MCP registry as com.usmortgagecalc/mortgage. US mortgage calculator and amortization API with 50-state property tax, PMI, and affordability data. This page covers its hosted endpoint (https://www.usmortgagecalc.com/mcp).
Is the US Mortgage Calculator MCP server safe to use?
US Mortgage Calculator scores 88 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.
What tools does the US Mortgage Calculator MCP server expose?
US Mortgage Calculator exposes 11 tools: calculate_mortgage, calculate_amortization, calculate_pmi, calculate_property_tax, calculate_affordability, and 6 more. Their descriptions and schemas cost roughly 2,574 tokens of context every time the server is loaded.
Does the US Mortgage Calculator MCP server require authentication?
No. We connected to US Mortgage Calculator without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the US Mortgage Calculator MCP server still maintained?
US Mortgage Calculator is still listed as active in the MCP registry. We last reached this channel on 20 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.