# Borrowology > A debt payoff calculator, collection letters, and credit-report guides. Nothing you type is sent. Educational reference only. Not financial or legal advice. Letters that cite the Fair Credit Reporting Act or the Fair Debt Collection Practices Act follow United States law. They cannot force a bureau to delete an accurate item, and they cannot stop a lawsuit. ## Tools - [Debt payoff calculator](https://borrowology.com/tools/payoff-matrix/): Compare snowball, avalanche, custom order, and minimum payments in the browser. - [Credit card payoff calculator](https://borrowology.com/tools/credit-card-payoff/): One balance, APR, and a date or a payment. APR divided by 12, same clock as snowball. - [Collection decision flow](https://borrowology.com/tools/collection-decision/): State, debt type, last payment, and what the collector sent. Not a ruling. - [Free credit report dispute letter](https://borrowology.com/tools/dispute-letter-generator/): A letter to Experian, Equifax, or TransUnion. Nothing is sent or saved. - [Goodwill letter for a late payment](https://borrowology.com/tools/goodwill-letter/): A courtesy request to a creditor. They can refuse. - [Debt validation letter](https://borrowology.com/tools/debt-validation-letter/): Ask a collector to verify a debt under 15 U.S.C. §1692g. Not an acknowledgment. - [Cease-contact letter](https://borrowology.com/tools/cease-contact-letter/): Tell a collector to stop contacting you. It does not stop a lawsuit. - [Pay-for-delete letter](https://borrowology.com/tools/pay-for-delete-letter/): A written side deal before you pay. They can refuse. - [Hardship letter](https://borrowology.com/tools/hardship-letter/): Ask a creditor for a reduced payment or pause. They can refuse. ## Guides - [What makes up your credit score](https://borrowology.com/credit-science/how-your-credit-score-is-made-up/): What makes up a credit score: FICO lists five components, led by payment history. Those weights are not a formula for an exact point change. - [Credit card statement date vs due date](https://borrowology.com/credit-science/statement-vs-due-date/): Credit card statement date vs due date: the closing date is the balance a bureau usually sees. The due date is when the payment must arrive. - [How to dispute a credit report error](https://borrowology.com/credit-science/dispute-mechanics-609/): How to dispute a credit report error under FCRA §611, and what a 609 letter asks a bureau to disclose. Neither request guarantees a deletion. - [How to freeze your credit for free](https://borrowology.com/credit-science/how-to-freeze-your-credit/): How to freeze your credit for free at Experian, Equifax, and TransUnion. A freeze blocks most new credit. It does not delete what is already on the report. - [What is a goodwill letter?](https://borrowology.com/credit-science/what-is-a-goodwill-letter/): A goodwill letter asks a creditor to remove an accurate late payment as a courtesy. It is not a dispute. The creditor can say no. - [I paid a collection. Will it come off my credit report?](https://borrowology.com/credit-science/i-paid-a-collection/): Paying a collection updates the status to paid. It does not take the item off a United States credit report. Pay-for-delete is a side deal before you pay. - [What a debt validation letter actually asks](https://borrowology.com/credit-science/debt-validation-letter/): A debt validation letter asks a United States collector to verify a debt under 15 U.S.C. §1692g. It is not an acknowledgment that you owe it. - [What a cease-contact letter does](https://borrowology.com/credit-science/cease-contact-letter/): A cease-contact letter tells a United States collector to stop contacting you under 15 U.S.C. §1692c(c). It does not stop a lawsuit. - [What a hardship letter to a credit card company is](https://borrowology.com/credit-science/hardship-letter/): A hardship letter asks a creditor for a reduced payment, a pause, or a program. It is a request. They can refuse. It is not a dispute. - [Debt snowball vs avalanche](https://borrowology.com/debt-mechanics/avalanche-vs-snowball/): Debt snowball vs avalanche: paying the highest rate first usually costs less interest. Paying the smallest balance first can clear an account sooner. - [How to calculate daily credit card interest](https://borrowology.com/debt-mechanics/how-credit-card-interest-is-calculated/): How to calculate a credit card’s daily interest rate: many cards use APR ÷ 365 on a daily balance. APR divided by 12 is a different monthly estimate. - [How long a debt stays on your credit report](https://borrowology.com/debt-mechanics/how-long-a-debt-stays-on-your-credit-report/): How long debt and collections stay on a United States credit report: most negatives run seven years from the delinquency, even after you pay. - [What does a balance transfer cost](https://borrowology.com/instruments/what-does-a-balance-transfer-cost/): What a balance transfer costs: the fee is often 3% or 5% of the amount moved, charged up front, and the low rate ends on the date in the offer. - [Does consolidating loans save money?](https://borrowology.com/instruments/does-consolidating-loans-save-money/): Does consolidating loans save money? A lower monthly payment can still cost more if the new rate, the fee, or the term is worse than the debts you have. - [What is a buy rate on a car loan?](https://borrowology.com/instruments/what-is-a-buy-rate-on-a-car-loan/): Buy rate meaning: the lender’s quote to the dealer. The sell rate, or contract APR, can be higher. See what the markup costs. - [Statute of limitations on debt](https://borrowology.com/statute-of-limitations/): Verified lawsuit deadlines for Texas, California, Florida, New York, and Illinois. Unverified clocks are not guessed. - [Credit glossary](https://borrowology.com/glossary/): Short definitions for the words used in the guides. ## Site - [Sitemap](https://borrowology.com/sitemap.xml): Every indexable URL. - [About](https://borrowology.com/about/): Who publishes the site. - [Contact](https://borrowology.com/contact/): Questions about a source or a tool. - [Terms](https://borrowology.com/terms/): Rules for using the site.