What is a law school index score?

It is a single number that blends your GPA and LSAT into one figure so an admissions office can screen applicants quickly. Each school sets its own coefficients, but the common public form weights the LSAT slightly more than GPA because the LSAT is a standardised, school-independent measure.

What formula does this use?

It normalises GPA to a 0-100 scale (GPA / 4.0 × 100) and LSAT to a 0-100 scale ((LSAT − 120) / 60 × 100), then combines them as 0.4 × normalised GPA + 0.6 × normalised LSAT. This mirrors the LSAT-weighted blend many schools publish, though exact coefficients vary.

Why is the LSAT weighted more heavily than GPA?

GPA varies by school and major, while the LSAT is identical for every applicant, so admissions committees treat it as the more comparable signal. Many index formulas therefore give the LSAT a coefficient of 0.6 or higher against 0.4 for GPA.

Is a higher index always better?

Yes for the numerical screen, but the index is only the first filter. Personal statements, recommendations, work experience, and diversity factors all influence the final decision, especially for applicants near a school's median.

Does each school use the same index?

No. Coefficients and even the variables differ between schools, and many do not publish their formula at all. Treat this index as a standardised proxy that lets you compare your own profile across schools on one consistent scale.

What is the Law School GPA/LSAT Index Calculator?

Enter your GPA and LSAT score to compute the weighted admissions index many law schools use as a primary numerical screen, plus your percentile position relative to typical applicant medians. It runs free in your browser on Gera Tools, with nothing uploaded.

Law School GPA/LSAT Index Calculator

Name: Law School GPA/LSAT Index Calculator
Creator: Gera Tools
License: https://creativecommons.org/licenses/by/4.0/

Law schools receive far more applications than they can read in depth, so almost every admissions office reduces your two hardest numbers — GPA and LSAT — to a single index score for an initial screen. This calculator builds that index using the common LSAT-weighted blend so you can compare your profile across schools on one consistent scale.

How it works

The two inputs live on different scales, so each is first normalised to 0-100, then combined with weights that favour the LSAT:

normGPA  = (GPA / 4.0) × 100
normLSAT = ((LSAT − 120) / 60) × 100      // LSAT runs 120–180

index = 0.4 × normGPA + 0.6 × normLSAT

Because the LSAT carries a coefficient of 0.6 against GPA’s 0.4, a strong test score can offset a modest GPA more than the reverse. The resulting index sits on a 0-100 scale that is comparable across applicants regardless of undergraduate institution or major.

What the index tells you — and what it doesn’t

The index is useful for relative positioning: comparing where you stand relative to a school’s median numbers, and deciding whether to invest in further LSAT preparation or focus application energy elsewhere. It does not capture:

Trend. An upward GPA trajectory (say, 3.2 in the first two years followed by 3.8 in the last two) reads very differently to an admissions reader than a flat 3.5, even though the LSAC cumulative GPA may be the same.
Major and school reputation. A 3.5 from an Ivy League engineering programme is interpreted differently than a 3.5 in an easier field at a less selective institution, even though the index treats them identically.
LSAT improvement across multiple sittings. LSAC reports all scores, but many schools now take the highest. This calculator uses one score, so use your highest reportable LSAT for the most favourable index.
Soft factors. Personal statement quality, work experience, letters of recommendation, demonstrated interest, and diversity considerations all influence outcomes significantly for borderline applicants.

Use the index as a threshold indicator — are your numbers in range for this school at all? — then spend your effort on the soft factors that differentiate candidates whose indices are similar.

LSAT score range and what score gains are worth

The LSAT runs from 120 (lowest) to 180 (highest). Scores below roughly 148 close most ABA-accredited schools. Above 160, most regional law schools become accessible. Above 170, T14 schools are competitive for applicants with a strong GPA.

One important asymmetry: at the upper end of the scale, the percentile difference per point is large. Moving from 163 to 170 covers a much larger percentile jump than moving from 148 to 155. Because the index weights the LSAT at 60%, improving by even a few points at the top of the scale can meaningfully shift your index, which is why many applicants with strong GPAs choose to prep heavily for the LSAT rather than applying with a first sitting score.

Example and notes

For example, an applicant with a 3.6 GPA and a 165 LSAT normalises to 90 and 75, giving an index of 0.4 × 90 + 0.6 × 75 = 81. Push the LSAT to 172 and the index climbs to roughly 88, illustrating why test prep often has higher leverage than the last fractions of a GPA point. Remember every school weights these factors differently and considers much more than the numbers, so use the index as a relative compass, not an admissions verdict.