What actually makes up your FICO score
Five factors, five different weights. Knowing the math tells you exactly where to spend your effort.
FICO has published the rough weights of the five inputs that drive your score for years: payment history (35%), amounts owed (30%), length of credit history (15%), new credit (10%), and credit mix (10%). VantageScore uses similar inputs with slightly different weights, but the priorities are the same.
Payment history is the heaviest input because lenders care most about whether you actually pay. One 30-day late drops a healthy score by 60 to 110 points. The good news: late marks fade as they age, and removing even one verifiable inaccurate late mark can produce a big score jump.
'Amounts owed' is mostly utilization — the percentage of your revolving credit limit you are using. Under 30% is the standard guideline; under 10% is where the highest scores live. Paying a card down to $0 before the statement closes is the single fastest score move most people can make.
Length of credit history rewards patience. The age of your oldest account, the age of your newest account, and the average age of all accounts all count. That is why closing your oldest credit card is almost always a mistake — even an unused card with no balance helps your score by staying open.
New credit and credit mix are smaller levers, but they matter when scores are close. Opening five accounts in a month signals risk. Having only one type of credit (say, just credit cards) keeps the mix score artificially low. Adding an installment account, like a credit-builder loan, can broaden the mix without a hard pull.