This page shows how to calculate percentage and letter grade out of 30 score using the Easy Grade Calculator. We walk throught the exact process and common mistakes so you can handle scores accurately. For example: 22 out of 30 as percentage and grade equals 73.33% making it easy to understand your test results correctly.
Exact Formula
Percentage = (Score ÷ 30) × 100
To get the percentage divide the obtained score by total points and multiply by 100. In this case obtained score is X and total points is 30.
Full Conversion Table (0–30)
Typical grading scale used below (may vary):
A = 90–100% | B = 80–89% | C = 70–79% | D = 60–69% | F = below 60%
| Score (X/30) | Percentage | Grade |
|---|---|---|
| 30/30 | 100% | A |
| 29/30 | 96.67% | A |
| 28/30 | 93.33% | A |
| 27/30 | 90% | A |
| 26/30 | 86.67% | B |
| 25/30 | 83.33% | B |
| 24/30 | 80% | B |
| 23/30 | 76.67% | C |
| 22/30 | 73.33% | C |
| 21/30 | 70% | C |
| 20/30 | 66.67% | D |
| 19/30 | 63.33% | D |
| 18/30 | 60% | D |
| 17/30 | 56.67% | F |
| 16/30 | 53.33% | F |
| 15/30 | 50% | F |
| 14/30 | 46.67% | F |
| 13/30 | 43.33% | F |
| 12/30 | 40% | F |
| 11/30 | 36.67% | F |
| 10/30 | 33.33% | F |
| 9/30 | 30% | F |
| 8/30 | 26.67% | F |
| 7/30 | 23.33% | F |
| 6/30 | 20% | F |
| 5/30 | 16.67% | F |
| 4/30 | 13.33% | F |
| 3/30 | 10% | F |
| 2/30 | 6.67% | F |
| 1/30 | 3.33% | F |
| 0/30 | 0% | F |
⚠️ Note: Letter grades may vary by school, country or grading policy.
Worked Examples
Example 1: 13 out of 30
- Formula: 13 ÷ 30 × 100
- Calculation: 0.4333 × 100
- Percentage: 43.33%
- Grade: F
Example 2: 18 out of 30
- Formula: 18 ÷ 30 × 100
- Calculation: 0.6 × 100
- Percentage: 60%
- Grade: D
Example 3: 20 out of 30
- Formula: 20 ÷ 30× 100
- Calculation: 0.6667 × 100
- Percentage: 66.67%
- Grade: D
Example 4: 25 out of 30
- Formula: 25 ÷ 30 × 100
- Calculation: 0.8333 × 100
- Percentage: 83.33%
- Grade: B
Common Mistakes When Converting X Out of 30
| Wrong Method | Correct Method | Why It’s Wrong |
|---|---|---|
| Dividing by 100 | Divide by 30 | 30 is the total score not 100 |
| Forgetting ×100 | Multiply after dividing | Without ×100, you get a decimal not a percent |
| Rounding too early | Round at the final step | Early rounding distorts the final grade |
| Assuming universal grade scales | Check your school policy | Grade boundaries differ by system |
This section alone eliminates most grading errors made by students.
Out of 30 Questions (Wrong Answers)
| Wrong Answers | Correct | Percentage | Grade |
|---|---|---|---|
| 0 | 30 | 100% | A |
| 1 | 29 | 96.67% | A |
| 2 | 28 | 93.33% | A |
| 3 | 27 | 90% | A |
| 4 | 26 | 86.67% | B |
| 5 | 25 | 83.33% | B |
| 6 | 24 | 80% | B |
| 7 | 23 | 76.67% | C |
| 8 | 22 | 73.33% | C |
| 9 | 21 | 70% | C |
| 10 | 20 | 66.67% | D |
| 11 | 19 | 63.33% | D |
| 12 | 18 | 60% | D |
| 13 | 17 | 56.67% | F |
| 14 | 16 | 53.33% | F |
| 15 | 15 | 50% | F |
| 16 | 14 | 46.67% | F |
| 17 | 13 | 43.33% | F |
| 18 | 12 | 40% | F |
| 19 | 11 | 36.67% | F |
| 20 | 10 | 33.33% | F |
| 21 | 9 | 30% | F |
| 22 | 8 | 26.67% | F |
| 23 | 7 | 23.33% | F |
| 24 | 6 | 20% | F |
| 25 | 5 | 16.67% | F |
| 26 | 4 | 13.33% | F |
| 27 | 3 | 10% | F |
| 28 | 2 | 6.67% | F |
| 29 | 1 | 3.33% | F |
| 30 | 0 | 0% | F |
Rounding Rules (Teachers Care About This)
- Round only the final percentage not the fraction.
- Example: 22/30 = 73.33% → usually shown as 73% or 73.3%.
- Do not round up grades automatically unless your school explicitly allows it.
- Some institutions round to whole numbers: others keep one decimal for accuracy.
Always follow the grading policy used by your school or board.
Popular Scores Out of 30
Below are the most searched scores out of 30.
18 out of 30
18 out of 30 equals 60% which is typically a D grade under a standard 10 point grading scale.
See full breakdown of 18 out of 30
21 out of 30
21 out of 30 equals 70% usually a C grade.
See detailed explanation of 21 out of 30
22 out of 30
22 out of 30 equals 73.33% commonly a C grade.
View complete guide for 22 out of 30
24 out of 30
24 out of 30 equals 80% generally a B grade.
Read full analysis of 24 out of 30
26 out of 30
26 out of 30 equals 86.67% typically a B grade.
See how 26 out of 30 affects your grade.
27 out of 30
27 out of 30 equals 90% usually an A grade.
Explore full details for 27 out of 30
28 out of 30
28 out of 30 equals 93.33% commonly an A grade.
View full explanation of 28 out of 30
29 out of 30
29 out of 30 equals 96.67% typically an A grade.
Read complete breakdown of 29 out of 30
25 out of 30
25 out of 30 equals 83.33% and B grade.
Check complete breakdown of 25 out of 30
23 out of 30
23 out of 30 equals 76.67% and C grade.
Check out complete score breakdown of 23 out of 30
Related Grading Hubs
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X Out of 40 As Grade and Percentage