Source: JNTUH R22 B.Tech Academic Regulations (official PDF) . SGPA formula from clause 9.8; grade points from clause 9.2. Checked 22 August 2026. The same arithmetic gives CGPA when you enter every semester's credits and grades together.
How SGPA and CGPA are calculated
Both use the same arithmetic. The only difference is what you put in.
SGPA — enter the credits and grade for each subject in one semester:
SGPA = Σ(credits × grade points) ÷ Σ(credits)
CGPA — enter every subject from every semester together, and the same formula gives your CGPA.
This is why the calculator above has an “add another subject” button rather than separate tools. Source: clauses 9.8 and 9.9 of the JNTUH R22 B.Tech Academic Regulations.
Worked example
Four subjects in one semester:
| Subject | Credits | Grade | Points | Credit points |
|---|---|---|---|---|
| Subject A | 4 | O | 10 | 40 |
| Subject B | 3 | A+ | 9 | 27 |
| Subject C | 3 | A | 8 | 24 |
| Subject D | 2 | B+ | 7 | 14 |
| Total | 12 | 105 |
SGPA = 105 ÷ 12 = 8.75
Why credits matter more than grades
This is the single most useful thing to understand about the formula: a grade in a 4-credit subject counts twice as much as the same grade in a 2-credit subject.
It means a poor grade in a high-credit core subject damages your SGPA far more than a poor grade in a low-credit elective — and it’s why, when you have limited revision time, the high-credit papers deserve it first.
The effect of a backlog
An F grade carries 0 grade points but its credits still count in the denominator. A single failed 4-credit subject alongside a 4-credit O grade gives (40 + 0) ÷ 8 = 5.00, not 10.
That is the arithmetic reason a backlog hurts so much, and why clearing one lifts your CGPA more than an extra good grade elsewhere.
Common questions
Which grade do I pick for a re-attempt? The grade that appears on your latest memo for that subject.
Do half credits work? Yes — enter 1.5 or 2.5 if your course uses them.
Does this store my data? No. Everything is calculated in your browser.
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