How Your Credit Score Is Calculated

By CreditMeadow Editorial Team · Updated October 16, 2026

Knowing how your credit score is calculated takes most of the mystery out of the number. A FICO Score is a three-digit number between 300 and 850 that lenders use to estimate how likely you are to repay what you borrow. It is calculated from the information in your credit report, and FICO groups that information into five categories, each with its own weight.

This guide walks through each of the five categories, what the score leaves out, and how to check the credit reports your score is built on.

The five credit score factors at a glance

FICO, the company that created the FICO Score, groups the data in your credit report like this:

Factor	Share of a FICO Score	What it looks at
Payment history	35%	Whether you have paid past credit accounts on time
Amounts owed	30%	How much you owe and how much of your available credit you use
Length of credit history	15%	How long your credit accounts have been open
New credit	10%	How often you have recently applied for or opened new accounts
Credit mix	10%	The types of credit you have, such as credit cards and installment loans

These percentages describe how important each category is in general. FICO notes that the importance of each category may vary from one person to another, because every credit report is different. The same event can affect two people differently: a new account, for example, has a larger effect on someone who doesn't have much other credit information.

Payment history (35%)

Payment history is the largest factor in a FICO Score. According to FICO, your track record of paying on time tends to be the strongest predictor of whether you will pay future debts as agreed.

This category looks at:

Payment information on credit cards, retail accounts, installment loans, mortgages and finance company accounts
How overdue any delinquent payments are, or were in the past
The amount still owed on delinquent accounts or collection items
The number of past-due items on your credit report
How much time has passed since any delinquency, collection item or bankruptcy
How many of your accounts are being paid as agreed

A few late payments are not an automatic "score-killer," and FICO says an overall good credit history can outweigh one or two late credit card payments. Serious items carry more weight. Bankruptcies can stay on a credit report for 7 to 10 years, depending on the type, and third-party collection accounts can stay for seven years from the original delinquency date. Older items count less than recent ones, so a steady record of on-time payments helps more the longer it lasts.

Amounts owed (30%)

Amounts owed covers how much debt you carry and how much of your available credit you are using. The second part, your credit utilization ratio on revolving accounts such as credit cards, matters more to your score than the dollar amount alone.

This category considers:

The total amount you owe on all accounts
The amounts owed on different types of accounts, such as credit cards versus installment loans
How many of your accounts have a balance
Your credit utilization ratio on revolving accounts
How much of each installment loan is still owed compared with the original loan amount

Using a high percentage of your available credit can signal that you are overextended, which is why high card balances can lower your score. One detail surprises many people: the balance on your credit report is typically the balance from your latest monthly statement, so it may not show $0 even if you pay your card in full every month. Our guide to credit utilization explains how the ratio is calculated and how to lower it.

Length of credit history (15%)

A longer credit history is generally positive for your score, but it is not required for a good one. FICO says even people who haven't had credit for long can have a high score if the rest of their credit report looks good.

This factor looks at:

The age of your oldest account, the age of your newest account and the average age of all your accounts
How long specific credit accounts have been open
How long it has been since you used certain accounts

Opening a new account lowers the average age of your accounts. That is one way the length of your credit history and new credit are connected.

New credit (10%)

When you apply for credit, the lender requests your credit report and an inquiry is placed on it. Inquiries remain on your credit report for two years, but FICO Scores only consider inquiries from the last 12 months. FICO's research shows that opening several new credit accounts in a short period represents greater risk, especially for people who don't have a long credit history.

Three points about inquiries are worth knowing:

Inquiries usually have a small impact on your score.
Many types of inquiries are ignored completely.
FICO Scores allow for "rate shopping" when you compare loan offers.

Checking your own credit report does not affect your FICO Scores, as long as you order it directly from a credit bureau or through an organization authorized to provide credit reports to consumers. Our guide to hard vs soft inquiries explains which credit checks count and how the rate-shopping allowance works.

Credit mix (10%)

Credit mix is the variety of credit accounts you have. FICO describes two broad types:

Revolving accounts give you some flexibility in how much you pay each month, above any minimum payment. Credit cards are the familiar example, and FICO also lists retail store cards, gas station cards and home equity lines of credit (HELOCs).
Installment accounts, such as mortgages, auto loans and student loans, usually require a fixed payment each month until the balance is paid off.

You don't need one of each. Because credit mix makes up only 10% of a FICO Score, FICO says it most likely won't be a key factor in whether you get credit. Asked whether it is worth a drop in your score to take out a small loan just to show you can manage payments, FICO answers "probably not," since credit mix is such a small part of the score.

What is not part of your credit score

Your FICO Score is calculated only from your credit report, with one exception: a specialty FICO version that can also consider bank account data you choose to share. The score leaves out many personal and financial details. According to FICO, it does not consider:

Your race, color, religion, national origin, sex or marital status
Your age
Where you live
Child or family support obligations
Your salary, occupation, title, employer, date employed or employment history
The interest rate charged on any of your accounts
The type of credit you are requesting

Lenders may still look at some of these, such as your income and how long you have worked at your job, when they make a credit decision. They are part of the application, not part of the score.

Why you have more than one credit score

There is no single credit score. Lenders choose which scoring model and version to use, and FICO itself notes that some lenders use different versions of the FICO Score, while others use another type of credit score altogether. The score you see on a statement or a website may not be the same one a lender uses. Our guide to what counts as a good credit score covers FICO's score ranges and the reasons scores differ.

The underlying data can differ as well. Each of the three nationwide credit bureaus, Equifax, Experian and TransUnion, keeps its own credit report on you, and FICO points out that not all lenders report to all three. A score calculated from one bureau's report can therefore differ from a score calculated from another's.

How to check the credit reports behind your score

Because your score is calculated from your credit reports, reviewing them is the most direct way to see what is driving it. Equifax, Experian and TransUnion have permanently extended a program that lets you check your credit report from each of them once a week for free at AnnualCreditReport.com. The Federal Trade Commission warns that other sites may charge you or may be set up to steal your personal information.

When you review a report, check that:

Every account listed belongs to you.
Balances, credit limits and payment statuses look right.
Accounts you closed are shown as closed.
There are no inquiries you don't recognize.

The first three are among the common errors the Consumer Financial Protection Bureau tells people to look for, and FICO suggests checking your reports for unauthorized inquiries. If something is wrong, the FTC recommends contacting both the credit bureau that shows the error and the business that reported the information. Our step-by-step guide on how to dispute a credit report error covers what to send and what happens next.

Key takeaways

A FICO Score ranges from 300 to 850 and is calculated from your credit report.
Payment history (35%) and amounts owed (30%) make up about two-thirds of the score.
Length of credit history (15%), new credit (10%) and credit mix (10%) make up the rest.
The weights describe the general picture; how much each factor matters can vary by person.
You can check your credit report from each nationwide bureau for free once a week at AnnualCreditReport.com.

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