Financial Loan Amortization Calculator
Available ActionsEach successful request consumes credits as outlined below.
Details
Full-featured financial loan calculator supporting 11 operations: payment calculation, principal estimation, term calculation, simple and compound interest, amortization schedules with CSV export, side-by-side loan comparison, DTI-based affordability analysis, refinance break-even evaluation, payoff acceleration modeling with extra and lump-sum payments, and APR-to-effective-rate conversion. Handles mortgages, auto loans, personal loans, and investment growth scenarios with configurable compounding, payment frequencies, interest-only periods, and balloon terms.
Use Cases
Mortgage payment planning,Auto loan payment estimation,Amortization schedule download,Debt payoff acceleration analysis,Refinance break-even evaluation,Simple and compound interest projection,Debt-to-income affordability checks,Balloon payment scenario modeling,Interest-only period planning,Loan comparison analysis
Connect Your Agent In 5 Min
Watch the setup guide for your platform
Or Install Locally
STDIO connector for Claude Code, Codex, Cursor, Zed, and other LLMs that require STDIO or custom connections. This lightweight connector routes requests to https://api.agentpmt.com/mcp. All tool execution happens in the cloud and the server cannot edit any files on your computer.
npm install -g @agentpmt/mcp-routeragentpmt-setupActions(11)
calculate_payment5cr8 params(3 required)Compute the periodic payment for an amortizing loan. Supports interest-only periods, balloon payments, and configurable payment/compounding frequencies.
calculate_payment5cr8 params(3 required)Compute the periodic payment for an amortizing loan. Supports interest-only periods, balloon payments, and configurable payment/compounding frequencies.
principalrequirednumberLoan principal amount
annual_raterequirednumberNominal annual interest rate in percent
yearsrequirednumberLoan term in years
payments_per_yearintegerPayment frequency per year
12compounding_per_yearintegerCompounding frequency per year
12future_valuenumberTarget future value after final payment
0balloon_paymentnumberBalloon amount due at maturity
0interest_only_periodsintegerNumber of interest-only payment periods at the start
0calculate_loan_principal5cr8 params(2 required)Calculate the maximum loan principal supported by a given periodic payment amount.
calculate_loan_principal5cr8 params(2 required)Calculate the maximum loan principal supported by a given periodic payment amount.
payment_amountrequirednumberPeriodic payment amount
annual_raterequirednumberNominal annual interest rate in percent
yearsnumberLoan term in years (provide years or target_periods or both)
target_periodsintegerTarget number of payment periods (alternative to years)
payments_per_yearintegerPayment frequency per year
12compounding_per_yearintegerCompounding frequency per year
12future_valuenumberTarget future value
0balloon_paymentnumberBalloon due at maturity
0calculate_term5cr5 params(3 required)Calculate the number of periods and years required to pay off a loan given principal, rate, and payment amount.
calculate_term5cr5 params(3 required)Calculate the number of periods and years required to pay off a loan given principal, rate, and payment amount.
principalrequirednumberLoan principal
annual_raterequirednumberNominal annual interest rate in percent
payment_amountrequirednumberPeriodic payment amount
payments_per_yearintegerPayment frequency per year
12compounding_per_yearintegerCompounding frequency per year
12simple_interest5cr3 params(3 required)Calculate simple (non-compounded) interest totals for a given principal, rate, and duration.
simple_interest5cr3 params(3 required)Calculate simple (non-compounded) interest totals for a given principal, rate, and duration.
principalrequirednumberPrincipal amount
annual_raterequirednumberAnnual interest rate in percent
yearsrequirednumberDuration in years
compound_interest5cr7 params(3 required)Calculate compound interest growth over time, optionally with periodic contributions. Supports configurable compounding frequency and contribution timing.
compound_interest5cr7 params(3 required)Calculate compound interest growth over time, optionally with periodic contributions. Supports configurable compounding frequency and contribution timing.
principalrequirednumberInitial principal amount
annual_raterequirednumberAnnual interest rate in percent
yearsrequirednumberInvestment duration in years
compounding_per_yearintegerCompounding frequency per year
12periodic_contributionnumberAmount added each contribution period
0contribution_frequency_per_yearintegerHow often contributions are made per year
12contribution_timingstringWhether contribution is made at period end or beginning
endamortization_schedule5cr16 params(3 required)Build a full amortization table with support for extra payments, one-time lump sums, interest-only periods, balloon payments, and optional CSV file export to cloud storage.
amortization_schedule5cr16 params(3 required)Build a full amortization table with support for extra payments, one-time lump sums, interest-only periods, balloon payments, and optional CSV file export to cloud storage.
principalrequirednumberLoan principal
annual_raterequirednumberNominal annual interest rate in percent
yearsrequirednumberLoan term in years
payments_per_yearintegerPayment frequency per year
12compounding_per_yearintegerCompounding frequency per year
12future_valuenumberTarget future value
0balloon_paymentnumberBalloon due at maturity
0interest_only_periodsintegerInterest-only period count
0extra_paymentnumberRecurring extra principal each period
0extra_payment_start_periodintegerPeriod to begin recurring extra payments
1one_time_extra_paymentsarrayList of one-time extra principal payments
start_datestringSchedule start date in YYYY-MM-DD format; adds date column to each row
return_schedulebooleanInclude schedule rows in response
truemax_schedule_rowsintegerMaximum amortization rows to return
5000store_schedule_filebooleanUpload schedule as CSV to cloud storage and return file metadata
falseexpiration_daysintegerCloud file expiration in days
7compare_loans5cr2 params(1 required)Compare multiple loan scenarios side-by-side and rank by selected metric (lowest payment, lowest interest, or lowest total cost).
compare_loans5cr2 params(1 required)Compare multiple loan scenarios side-by-side and rank by selected metric (lowest payment, lowest interest, or lowest total cost).
compare_scenariosrequiredarrayLoan scenarios to compare (minimum 2 required)
comparison_metricstringHow to rank scenarios
lowest_total_costaffordability_analysis5cr13 params(3 required)Estimate affordable monthly payment, maximum loan principal, and maximum home price based on income, debts, and DTI ratios.
affordability_analysis5cr13 params(3 required)Estimate affordable monthly payment, maximum loan principal, and maximum home price based on income, debts, and DTI ratios.
annual_incomerequirednumberGross annual income
annual_raterequirednumberExpected mortgage rate in percent
yearsrequirednumberLoan term in years
monthly_debtsnumberRecurring monthly debt obligations
0monthly_expensesnumberAdditional recurring monthly expenses
0front_end_rationumberMaximum housing expense ratio to gross income
0.28back_end_rationumberMaximum total debt ratio to gross income
0.36property_tax_monthlynumberEstimated monthly property tax
0insurance_monthlynumberEstimated monthly insurance
0hoa_monthlynumberEstimated monthly HOA fees
0down_paymentnumberDown payment amount (added to max principal for max home price)
0payments_per_yearintegerPayment frequency per year
12compounding_per_yearintegerCompounding frequency per year
12refinance_break_even5cr7 params(6 required)Estimate payment savings, break-even period, and net lifetime benefit of refinancing a loan.
refinance_break_even5cr7 params(6 required)Estimate payment savings, break-even period, and net lifetime benefit of refinancing a loan.
current_balancerequirednumberCurrent remaining loan balance
current_raterequirednumberCurrent annual interest rate in percent
current_remaining_term_monthsrequiredintegerRemaining months on current loan
new_raterequirednumberNew annual interest rate in percent
new_term_monthsrequiredintegerNew loan term in months
closing_costsrequirednumberRefinance closing costs
current_paymentnumberCurrent monthly payment (if omitted, calculated automatically from balance/rate/term)
payoff_acceleration5cr12 params(3 required)Model interest and term savings from recurring and one-time extra payments by comparing baseline vs accelerated payoff scenarios.
payoff_acceleration5cr12 params(3 required)Model interest and term savings from recurring and one-time extra payments by comparing baseline vs accelerated payoff scenarios.
principalrequirednumberLoan principal
annual_raterequirednumberNominal annual interest rate in percent
yearsrequirednumberOriginal loan term in years
payments_per_yearintegerPayment frequency per year
12compounding_per_yearintegerCompounding frequency per year
12extra_paymentnumberRecurring extra principal each period
0extra_payment_start_periodintegerPeriod to begin recurring extra payments
1one_time_extra_paymentsarrayOne-time extra payments
future_valuenumberTarget future value
0balloon_paymentnumberBalloon due at maturity
0interest_only_periodsintegerInterest-only period count
0start_datestringOptional start date in YYYY-MM-DD format
rate_conversion5cr3 params(1 required)Convert a nominal annual percentage rate (APR) into effective annual, payment-period, and daily effective rates.
rate_conversion5cr3 params(1 required)Convert a nominal annual percentage rate (APR) into effective annual, payment-period, and daily effective rates.
annual_raterequirednumberNominal annual interest rate in percent
compounding_per_yearintegerCompounding frequency per year
12payments_per_yearintegerPayment frequency per year
12curl -X POST "https://api.agentpmt.com/products/purchase" \
-H "Content-Type: application/json" \
-H "Authorization: Bearer ********" \
-d '{
"product_id": "69858a60269243768b447d61",
"parameters": {
"action": "calculate_payment",
"principal": 0,
"annual_rate": 0,
"years": 0,
"payments_per_year": 12,
"compounding_per_year": 12,
"future_value": 0,
"balloon_payment": 0,
"interest_only_periods": 0
}
}'import requests
import json
url = "https://api.agentpmt.com/products/purchase"
headers = {
"Content-Type": "application/json",
"Authorization": "Bearer ********"
}
data = {
"product_id": "69858a60269243768b447d61",
"parameters": {
"action": "calculate_payment",
"principal": 0,
"annual_rate": 0,
"years": 0,
"payments_per_year": 12,
"compounding_per_year": 12,
"future_value": 0,
"balloon_payment": 0,
"interest_only_periods": 0
}
}
response = requests.post(url, headers=headers, json=data)
print(response.status_code)
print(response.json())const url = "https://api.agentpmt.com/products/purchase";
const headers = {
"Content-Type": "application/json",
"Authorization": "Bearer ********"
};
const data = {
product_id: "69858a60269243768b447d61",
parameters: {
"action": "calculate_payment",
"principal": 0,
"annual_rate": 0,
"years": 0,
"payments_per_year": 12,
"compounding_per_year": 12,
"future_value": 0,
"balloon_payment": 0,
"interest_only_periods": 0
}
};
fetch(url, {
method: "POST",
headers: headers,
body: JSON.stringify(data)
})
.then(response => response.json())
.then(data => console.log(data))
.catch(error => console.error("Error:", error));const axios = require('axios');
const url = "https://api.agentpmt.com/products/purchase";
const headers = {
"Content-Type": "application/json",
"Authorization": "Bearer ********"
};
const data = {
product_id: "69858a60269243768b447d61",
parameters: {
"action": "calculate_payment",
"principal": 0,
"annual_rate": 0,
"years": 0,
"payments_per_year": 12,
"compounding_per_year": 12,
"future_value": 0,
"balloon_payment": 0,
"interest_only_periods": 0
}
};
axios.post(url, data, { headers })
.then(response => {
console.log(response.status);
console.log(response.data);
})
.catch(error => {
console.error("Error:", error.message);
});Login to view your API and budget keys. The example above uses placeholder values. Sign in to see personalized code with your bearer token.
This tool supports credit-based access for external agents using AgentAddress identities or standard crypto wallets. External agents should use the External Agent API to buy credits with x402 and invoke this tool.
1. Buy Credits
Purchase credits via x402 payment (500 credit minimum, 100 credits = $1).
# Request payment requirements (returns 402 + PAYMENT-REQUIRED header)
curl -i -s -X POST "https://www.agentpmt.com/api/external/credits/purchase" \
-H "Content-Type: application/json" \
-d '{ "wallet_address":"0xYOUR_WALLET", "credits": 500, "payment_method":"x402" }'
# Sign the EIP-3009 authorization, then retry with signature header
curl -s -X POST "https://www.agentpmt.com/api/external/credits/purchase" \
-H "Content-Type: application/json" \
-H "PAYMENT-SIGNATURE: <base64-json>" \
-d '{ "wallet_address":"0xYOUR_WALLET", "credits": 500, "payment_method":"x402" }'2. Create a Session Nonce (nonce used in signed balance/invoke)
curl -s -X POST "https://www.agentpmt.com/api/external/auth/session" \
-H "Content-Type: application/json" \
-d '{ "wallet_address":"0xYOUR_WALLET" }'3. Invoke This Tool
Sign the message with your wallet (EIP-191 personal-sign), then POST to the invoke endpoint.
# Sign this message (wallet MUST be lowercased):
# agentpmt-external
# wallet:0xyourwallet...
# session:<session_nonce>
# request:<request_id>
# action:invoke
# product:69858a60269243768b447d61
# payload:<sha256(canonical_json(parameters))>
curl -s -X POST "https://www.agentpmt.com/api/external/tools/69858a60269243768b447d61/invoke" \
-H "Content-Type: application/json" \
-d '{
"wallet_address": "0xYOUR_WALLET",
"session_nonce": "<session_nonce>",
"request_id": "invoke-uuid",
"signature": "0x<signature>",
"parameters": {
"action": "your_action",
"your_param": "value"
}
}'About The Developer
Apoth3osis
Joined Agent Payment: August 14, 2025
We build tools that enable AI agents to excel in the mathematical realm.
Our small team develops experimental and unique solutions in the AI arena, with a strong focus on modular computing for agentic applications and custom model deployment. We have handled projects for a variety of applications across many sectors, from algorithmic trading and financial analysis, to molecular simulations and predictions, to habitat and biodiversity monitoring and wildlife conservation.