GPA Scale Explained — 4.0, 5.0, and Weighted Systems (2026 Guide)

Originally published at bestgpacalculator.online.

A GPA scale is the conversion table that turns letter grades into the numeric value that gets averaged into your grade point average. The 4.0 scale is the US default, but it isn't the only one — high schools weight Honors and AP classes on a 5.0 scale, some elite private schools use 4.3 or even 4.33, and international transcripts use entirely different number ranges. This post lays out every scale you'll see on a real US transcript, shows the letter conversion for each, and explains how to compare a GPA across systems without losing your mind.

The 50-word version

The standard US college GPA scale is 4.0, where A=4.0, B=3.0, C=2.0, D=1.0, F=0. High schools commonly use a weighted 5.0 scale that gives Honors and AP classes a +0.5 or +1.0 bonus. Some schools use 4.3 (A+ = 4.3) or 4.33 scales. Use a weighted GPA calculator for AP/Honors-heavy schedules and an unweighted GPA calculator when you need the standardized version.

The standard 4.0 unweighted scale

This is the scale that almost every US college, every job application, and every standardized GPA conversion uses as the baseline. It maps every letter grade to a number between 0.0 and 4.0:

Two things to notice:

1. A+ does not exceed 4.0 on the standard scale. Some schools award an A+ but cap the GPA value at 4.0, so a transcript full of A+'s still tops out at a 4.0 cumulative.
2. The percentage ranges vary by district. A score of 92% might be an A- in one high school and an A in another. The letter is what gets converted, not the raw percentage.

The 4.0 scale is what colleges, grad schools, scholarship committees, and employers expect to see. If a form just says "GPA" with no qualifier, it means the 4.0 unweighted scale.

The weighted 5.0 scale (high school)

High schools that offer Honors, AP, IB, and sometimes Dual Enrollment classes use a weighted scale that gives extra credit for taking harder coursework. The most common version is the 5.0 weighted scale:

The same letter scaling applies — B+ in an AP class is 4.3 on a 5.0 scale (3.3 unweighted + 1.0 weighting bonus). The exact weighting differs by district:

• +1.0 for AP, +0.5 for Honors (most common — pushes max GPA to 5.0)
• +0.5 for both AP and Honors (more conservative — pushes max to 4.5)
• +1.0 for AP, +1.0 for Honors (a few districts — pushes max to 5.0 for any honors course)

You can hit a weighted GPA above 4.0 — sometimes well above — by taking heavy AP/Honors loads. A student with all A's in 8 AP classes can post a 5.0 weighted while their unweighted GPA is 4.0.

The 4.3 and 4.33 scales

Some high schools and a smaller number of US colleges (often private liberal arts and a handful of elite institutions) use a scale that goes up to 4.3 or 4.33, treating A+ as worth more than a plain A:

The difference is small in absolute terms — only the A+ value changes — but it matters for class rank and for valedictorian eligibility. If your school uses a 4.3 or 4.33 scale and you're applying to colleges that report on a 4.0 scale, list both with the scale labeled: GPA: 4.05 / 4.3. Admissions officers know how to read it.

The 5.0 unweighted scale (rare)

A small number of schools — mostly competitive magnet high schools and a few private institutions — use a 5.0 unweighted scale where A=5, B=4, C=3, D=2, F=1. This is unusual enough that you should always note the scale: GPA: 4.6 / 5.0 (unweighted). Without the qualifier, anyone reading the resume will assume the 4.0 standard and think you're inflating.

The 100-point scale

Some high schools, especially in New York State and the southern US, report grades as a 0-100 percentage and never convert to a 4.0 GPA on the transcript at all. Colleges that receive these transcripts do the conversion internally. If you need to convert for a resume or application, the rough mapping is:

For more precise conversion, use a percentage to GPA calculator.

International GPA scales

If you studied outside the US, your transcript will use whatever system your country uses, and you'll need to convert to a 4.0 scale for US applications.

• UK degree classifications: First Class = 4.0, Upper Second (2:1) = 3.5-3.7, Lower Second (2:2) = 3.0-3.3, Third = 2.5
• Indian percentage / CGPA: 90%+ usually converts to 4.0, 80-89% to 3.5-3.7, 70-79% to 3.0-3.3. CGPA on a 10-point scale divides differently — a 9.0 CGPA is roughly 3.7 on a US 4.0 scale
• German Notenskala (1-5 scale, where 1 is best): 1.0 = 4.0, 1.5 = 3.7, 2.0 = 3.3, 2.5 = 3.0, 3.0 = 2.5
• Australian / New Zealand 7-point GPA: 7 = 4.0, 6 = 3.5, 5 = 3.0, 4 = 2.0

US grad school applications usually require a WES (World Education Services) evaluation that does this conversion officially.

How to read a GPA when the scale isn't labeled

If someone hands you a GPA without saying which scale, use these defaults:

1. GPA between 0 and 4.0 → 4.0 unweighted scale, almost certainly
2. GPA between 4.0 and 5.0 → weighted high school GPA, on a 5.0 scale
3. GPA exactly 4.0 → could be a perfect unweighted, or weighted but not maxed out — ask
4. GPA above 5.0 → unusual; probably a different scale (some districts use 6.0 weighted) or a typo
5. GPA listed as 4.3, 4.33, or with that range → 4.3 scale, A+ awarded
6. GPA listed with "/" notation (e.g., 3.7/4.0) → the denominator is the scale; trust it

When in doubt, ask. A 3.8 GPA on a 5.0 weighted scale is a much weaker signal than a 3.8 on a 4.0 unweighted scale.

Which scale do colleges use to evaluate applicants?

Most college admissions offices recalculate your high school GPA on their own scale before reviewing. The University of California system has its own formula. Most Common App schools convert to a 4.0 unweighted and use that as the primary comparison number, then look at the weighted GPA as supporting context for course rigor.

What this means practically:

• A weighted 4.6 with a strong AP load and a recalculated 3.9 unweighted will read better to admissions than a weighted 4.6 with a 3.6 unweighted
• The course difficulty itself (AP/IB/Honors) is a separate evaluation factor from the GPA number
• Self-reported GPA on the Common App should use what your high school transcripts list, with the scale specified

Quick reference card

Common pitfalls

• Reporting a weighted GPA without the qualifier. A 4.5 weighted looks like a typo or inflation if you don't say "weighted, 5.0 scale." Always label
• Rounding the wrong way. GPA scales convert exactly — your 3.467 cumulative rounds to 3.47, not 3.5
• Mixing scales mid-resume. If you list your high school weighted GPA and your college unweighted GPA on the same page, label both
• Assuming all 4.0 scales convert identically. A 4.0-scale school that doesn't award + or - grades will produce slightly different cumulatives than one that does

Originally published at bestgpacalculator.online/blog/gpa-scale-explained. For more on the mechanics, see How Weighted GPA Works, Weighted vs Unweighted GPA, and The 4.0 GPA Scale Explained.