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Grading Scale Calculator

Generate a complete letter grade scale for any test or assignment. Choose a standard 10-point scale, a plus/minus scale, or set your own custom cutoffs — with score ranges calculated automatically from your total points.

GradePercentage RangeScore RangeRange Width
A+97–100%39–40 pts
4 pts wide
A93–96%38 pts
4 pts wide
A−90–92%36 pts
3 pts wide
B+87–89%35 pts
3 pts wide
B83–86%34 pts
4 pts wide
B−80–82%32 pts
3 pts wide
C+77–79%31 pts
3 pts wide
C73–76%30 pts
4 pts wide
C−70–72%28 pts
3 pts wide
D+67–69%27 pts
3 pts wide
D63–66%26 pts
4 pts wide
D−60–62%24 pts
3 pts wide
F0–59%0–23 pts
59 pts wide
13 grades · 40 total points

Standard US Grading Scale

The 10-point grading scale is the most widely used in US K–12 and higher education. Each letter grade covers a 10-percentage-point range, with F covering everything below 60%.

Letter GradePercentageGPA ValueDescription
A90–100%4.0Excellent
B80–89%3.0Good
C70–79%2.0Average
D60–69%1.0Below Average
F0–59%0.0Failing

Plus/Minus Grading Scale

The plus/minus scale subdivides each letter grade into three tiers and is the standard at most US colleges and universities. Each tier carries a distinct GPA value.

Letter GradePercentageGPA Value
A+97–100%4.0
A93–96%4.0
A−90–92%3.7
B+87–89%3.3
B83–86%3.0
B−80–82%2.7
C+77–79%2.3
C73–76%2.0
C−70–72%1.7
D+67–69%1.3
D63–66%1.0
D−60–62%0.7
F0–59%0.0

Minimum Score Needed by Test Size

How many questions you need to get right (standard 10-point scale) to earn each letter grade, by total number of questions.

GradeMin %10q20q25q30q40q50q100q
A90%9182327364590
B80%8162024324080
C70%7141821283570
D60%6121518243060

Common Custom Grading Scales

Not all schools use the standard 10-point scale. Here are the most common variations used in US schools and colleges.

7-Point Scale

Some K–12 districts

A=93, B=85, C=77, D=70, F=below 70. Common in some Southern US states and competitive programs. Tighter B and C ranges.

8-Point Scale

Some colleges

A=92, B=84, C=76, D=68, F=below 68. Less common; sits between the 7-point and standard scales.

6-Point Scale

Selective programs

A=94, B=86, C=78, D=70, F=below 70. Used by some universities that want a stricter A threshold.

Pass/No Pass

Grad school, clinicals

Binary — students either pass (typically 70%+) or do not. No letter grade awarded. Common for electives, clinicals, and some graduate courses.

100-Point Scale

Individual teachers

Some teachers grade on a 100-point scale but use non-standard cutoffs — e.g., A=95+ to make As harder to earn.

Percentage Only

AP / IB courses

Some teachers report only a percentage, not a letter grade. Use this calculator to look up what any percentage corresponds to.

Frequently Asked Questions

Common questions about grading scales, letter grade percentages, and how grades are calculated.

What percentage is an A grade?

On the standard 10-point grading scale used by most US schools, an A is 90–100%. On a plus/minus scale, an A is 93–96%, an A+ is 97–100%, and an A− is 90–92%. Some schools use a 7-point or 8-point scale where an A starts at 92% or 93%. Always check your specific school or teacher's syllabus for the exact cutoffs.

What is the standard grading scale in the US?

The most common US grading scale uses 10-point intervals: A (90–100%), B (80–89%), C (70–79%), D (60–69%), and F (below 60%). Many colleges and high schools use a plus/minus variation that subdivides each letter grade — for example, B+ (87–89%), B (83–86%), B− (80–82%). Private schools and some universities may use their own custom scales.

What is a plus/minus grading scale?

A plus/minus grading scale subdivides each letter grade into three tiers: plus, neutral, and minus. For example, instead of just "B" for 80–89%, you get B+ (87–89%), B (83–86%), and B− (80–82%). This gives more granularity and is used by most colleges and many high schools. Plus/minus grades typically carry different GPA values — a B+ = 3.3 GPA while a B = 3.0 and B− = 2.7.

How do I set up a custom grading scale?

Switch to the "Custom" tab and enter the minimum percentage for each letter grade. For example, if you want to set A at 88%, B at 76%, C at 64%, D at 52%, enter those values and the calculator instantly generates the full scale with score ranges based on your total points. This is useful for teachers who curve their tests or use non-standard cutoffs.

What is a 7-point grading scale?

A 7-point grading scale compresses the ranges compared to the standard 10-point scale: A (93–100%), B (85–92%), C (77–84%), D (70–76%), F (below 70%). This scale is often considered slightly more lenient for the A range but stricter for B and C. To use a 7-point scale with this calculator, switch to Custom mode and enter your specific cutoffs.

How do I calculate scores from percentages?

To find the minimum score for a given grade, multiply the percentage cutoff by the total number of points and round up. For example, on a 40-question test with an A cutoff at 90%: 40 × 0.90 = 36, so a student needs at least 36 correct to earn an A. This calculator does that math automatically — just enter your total points and the score column updates instantly.

What percentage do you need to pass a class?

In most US schools, a passing grade is a D− or above, which typically corresponds to 60% or higher. However, many programs — especially in nursing, education, and engineering — require a C or 73% to receive course credit toward the major. Graduate programs often require a B or 80% to remain in good standing. Check your specific program's requirements.

Is a 70% a passing grade?

Yes — on the standard US grading scale, 70% is a C−, which is a passing grade. However, whether a C− is acceptable depends on context. For a general elective, it passes. For a prerequisite course in your major, your program may require a C (73%) or higher. For graduate courses, a C− is often below the minimum required to keep credit.