Your Gail Model Assessment

7 questions · takes about 2 minutes · nothing is stored or shared

1 About you

Current age

yrs

The Gail Model applies to
women aged 35 and older.

Ethnicity

Breast cancer incidence varies across ethnicities — this helps calibrate the baseline risk estimate.

2 Menstrual history

Age at first menstrual period (menarche)

Earlier onset is associated with a small increase in breast cancer risk due to longer lifetime oestrogen exposure.

3 Reproductive history

Age at first live birth

Never having given birth, or having a first birth after age 30, is a modest risk factor due to hormonal patterns during pregnancy.

4 Family history

First-degree relatives diagnosed with breast cancer

This means your mother, sisters, or daughters only. Half-siblings count if they share a biological parent.

Important: If 2 or more relatives are affected — especially if any were diagnosed young (under 50) or have ovarian cancer — the Gail Model may significantly underestimate your risk. Ask your doctor about a BRCA gene test and consider a hereditary risk tool such as Tyrer-Cuzick or BOADICEA.

5 Biopsy history

Previous breast biopsies

Includes core needle, surgical, or other biopsy of breast tissue — not fine needle aspirations.

Did any biopsy show atypical hyperplasia?

Atypical ductal or lobular hyperplasia substantially increases risk. If you're unsure, your pathology report will state this.

6 Dense breasts New 2024

Have you been told you have dense breast tissue on a mammogram?

Since September 2024 (US), all mammography facilities must disclose breast density. Dense tissue increases risk by 1.2–2× and can obscure tumours on standard mammograms.

🩷

Your personalised risk estimate

Complete the 6 sections on the left. Your 5-year risk, lifetime estimate, and personalised screening recommendations will appear here.

Your estimated 5-year breast cancer risk

—%

chance of developing breast cancer in the next 5 years

—%

average for women your age

—×

your risk vs. average

👩

—

Your risk on the population scale

Below average Average Above average High

Below avg

<0.8%

Average

0.8–1.9%

Above avg

2.0–2.9%

High

3.0%+

—

Lifetime perspective

—%

Estimated lifetime risk (to age 90) based on your profile

~12%

Average lifetime risk for women in the general population

Personalised screening recommendations 2024–25 Guidelines

What this calculator doesn't account for

Paternal family history (father's side, aunts, grandmothers) — the Gail Model uses maternal first-degree relatives only. Paternal risk is clinically significant and should be discussed with your doctor.

Known BRCA1 or BRCA2 gene mutations — the Gail Model significantly underestimates risk in carriers. If you know you carry a BRCA variant, this result is not applicable to you.

Prior history of DCIS (ductal carcinoma in situ) or lobular carcinoma in situ (LCIS) — these substantially alter risk and require specialist risk stratification.

Hormone replacement therapy (HRT), obesity, alcohol use, exercise — these modifiable factors affect risk and are covered by newer models such as Tyrer-Cuzick.

The Gail Model has known limitations in accuracy for non-white women; the NCI has published ethnicity-adjusted models. Your estimate has been adjusted, but please treat it as indicative rather than precise.

Your next step: talk to your doctor

No online tool can replace a clinical conversation. Bring this result to your next GP or gynaecology appointment — they can confirm your risk category, order a mammogram if you haven't had one, and advise on whether more detailed genetic or imaging assessment is right for you.

Try the official NCI Gail Tool ↗

📅 Updated 2024–2025

What changed in breast cancer screening guidelines

Screening guidelines shifted significantly in 2024–2025, with major organisations recommending earlier and more personalised screening.

ACS 2024Annual mammograms starting at age 40 for all women of average risk. Women with above-average or high risk should begin earlier and may need supplemental MRI.

USPSTF 2024Updated final recommendation: biennial mammograms starting at age 40 for average-risk women (moved from 50). High-risk women should discuss earlier, more frequent screening.

FDA 2024Mandatory breast density disclosure on all mammography reports since September 10, 2024 across all US facilities — the first federal-level density notification standard.

ACS 2025Updated guidance on supplemental MRI for women with dense breasts who are at intermediate risk (15–20% lifetime) — previously only recommended for >20% lifetime risk.

Important medical disclaimer: This calculator implements the Gail Model for informational and educational purposes only. It is not a medical test and does not diagnose cancer. Risk estimates are statistical probabilities for populations, not predictions for individuals. Many women with high risk scores never develop breast cancer; some women with low scores do. Please always consult a qualified healthcare professional for personalised medical advice.