How the Simulator Works

This page explains the logic behind the estimates you see, so you can make smarter decisions. We keep the math transparent, conservative, and educational—it is not a replica of any proprietary scoring model.

1) What We’re Estimating

The simulator produces a directional estimate of how your score might shift when common credit events happen (for example, a missed payment or a utilization change). We start from your entered baseline score and apply weighted adjustments based on factors that typically influence credit scoring.

Quick reminder: Real lenders and bureaus use different versions of scoring models. The same profile can show different numbers across FICO® versions or VantageScore® models. This tool aims to teach what tends to move the needle and by how much—approximately.

2) The Factors We Model

Payment History

Payment history is the heaviest lever. A fresh 30‑day late often causes a noticeable dip; 60/90‑day lates are more severe. A clean 12‑month streak is one of the strongest positive signals.

Credit Utilization

The ratio of reported balances to total limits on revolving accounts. We nudge estimates negative above ~30% and slightly positive when you’re under ~10%, especially for profiles below prime.

New Credit & Inquiries

Hard inquiries and newly opened accounts can cause small short‑term dips. Clustering mortgage/auto inquiries within a short shopping window can mitigate impact in some models.

Age of Credit

Average age tends to help when it’s higher. Opening a new account can trim average age temporarily; spacing applications avoids compounding the dip.

Derogatory Marks

Collections and bankruptcies are modeled with heavier negative adjustments. Time and clean history help recovery.

On‑Time Streak

We model a small positive reinforcement for recent on‑time payments (last 12 months) because momentum matters.

3) Our Heuristic Weights (Transparent)

We translate the controls you set into a simple scoring “delta.” These are the core weights used by the simulator (expressed as directional educational magnitudes, not official points):

FactorHeuristic WeightNotes
UtilizationUp to ~−60 → +12 (scaled)Penalty grows progressively above ~30%; slight boost <10%.
Missed Payment30d: ~−18%; 60d: ~−28%; 90d+: ~−40%Modeled as stronger negatives with severity.
Hard Inquiries~−4 per inquiry (capped)Small, short‑term effect.
New Card~−3Small dip; may help utilization later.
Average‑Age Drop~−6 per year (capped)We cap the impact to avoid outsized effects.
On‑Time MonthsUp to ~+10Scaled by months out of 12.
DerogatoryCollection: heavy; Bankruptcy: heavierApplied as larger negatives.

4) Sensitivity by Starting Score

Profiles at lower scores can move upward faster with improvements, while high scores can be more rigid. We add a sensitivity multiplier to reflect this:

  • Sub‑prime (<620): slightly higher sensitivity to improvements and penalties.
  • Near‑prime (620–719): moderate sensitivity.
  • Prime (720+): lower sensitivity—smaller visible swings.

5) Worked Examples (Walkthroughs)

Example A — Lowering Utilization

Start: 690 baseline, 58% utilization, no recent lates or inquiries.

Action: Pay down balances to 18% before statement cut.

Why it helps: Big utilization drop moves a high‑signal factor from a negative bucket to a neutral/positive bucket.

Example B — A Single 30‑Day Late

Start: 735 baseline, 12% utilization, 12/12 on‑time months.

Event: One new 30‑day late.

Impact: A noticeable negative dip. Recovery improves with a new on‑time streak and low utilization over 6–12 months.

6) Why Your Number Can Differ From “Real” Scores

  • Different model versions (FICO® 8 vs. FICO® 10 vs. VantageScore).
  • Different bureaus, report dates, and data furnishers.
  • Unique profile details not captured by a simple simulator (closed accounts, charge‑offs, utilization by individual card, etc.).

7) Privacy & Data

This simulator runs entirely in your browser. We do not fetch your personal credit report and we do not perform any credit pulls. See the Privacy Policy for details about analytics and ads.

8) Calibration Philosophy

We designed the magnitudes to be conservative, and to teach directional cause‑and‑effect. If you lower utilization dramatically or avoid fresh derogatories, the simulator should reflect meaningful improvement—especially for profiles below prime.

9) Limitations (Read This)

Not financial advice: Use this tool for learning and planning. Always check official scores with your provider before major applications.

10) Quick FAQ

Does using the site affect my credit?

No. The simulator never pulls your credit. Everything runs locally in your browser.

Do all lenders use the same model?+

No. Lenders and bureaus use different versions; some even use custom overlays. Expect differences.

Is utilization per‑card or overall?+

Both can matter. This simulator uses an overall knob; per‑card spikes can weigh more in some models.

11) Mini‑Glossary

  • Statement Cut: The snapshot date when a lender reports balances.
  • Goodwill Letter: A request to remove a late after a strong history.
  • Thin File: A credit profile with few accounts or limited history.

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