What is CGPA?

CGPA is built in two stages, and the same operation runs at both levels. First each semester produces an SGPA from its subjects. Then those semesters produce a CGPA. The weight at the lower level is a subject’s credits; at the upper level it is the whole semester’s credits.

Start with one semester. Five subjects, their grade points, and their credits:

The SGPA is 115 ÷ 14 = 8.21. Note what the plain average would have said: 9, 8, 7, 10 and 6 average to exactly 8.00. The weighted figure is higher because the 10 came from a two-credit laboratory and the 6 from a one-credit compulsory course — small weights, so they move the result less than their face value suggests.

Now four semesters, each with its own SGPA and its own credit load:

The CGPA is 774.2 ÷ 94 = 8.23. The plain average of 7.80, 8.10, 8.60 and 8.40 is 8.22 — close here, because the four credit loads are close. Put one 30-credit project semester at a weak grade into the same degree and the two figures separate by half a point. The CGPA calculator runs the upper stage and the SGPA calculator the lower one, both showing the substitution with your own numbers.

A credit is a unit of teaching time, not of difficulty. The usual convention is one credit per hour of lecture per week for a semester, with laboratory and practical hours counted at half or a third of that — which is why a three-hour weekly lab is often worth one credit and a three-hour weekly theory course is worth three.

The practical consequence is that credits are decided by your syllabus, not by how hard you found the subject. A subject you spent the whole semester on can be worth two credits, and one you barely attended can be worth four. The arithmetic does not care.

People check their own arithmetic, find a gap of a tenth or two, and assume the calculator is wrong. Usually it is neither. Four things account for almost every mismatch.

1. Backlogs. A subject cleared in a later attempt normally enters the semester in which it was cleared, at the grade obtained. Some universities also cap the grade awarded on a re-attempt. Both pull a strong later semester down, and neither is visible from the outside.
2. Per-subject rounding. Your college awards a grade point per subject from marks bands, then averages. Anything that works from an aggregate skips that rounding step.
3. Audit and non-credit courses. They appear on the transcript with a grade and carry zero credits, so they contribute nothing. Including them by mistake shifts the figure.
4. Revaluation and improvement. A revised grade changes the semester it belonged to, so a CGPA computed from an older grade card is simply stale.

Where your figure and the university’s disagree, the university is right. Everything on this site is an estimate; your transcript is the record.

The percentage column below uses the general ten-point convention, (CGPA − 0.75) × 10, which is the default on this site because it is the least wrong when the issuing university is unknown. Your own university almost certainly publishes a different one — Anna University multiplies by 10, Mumbai University applies (CGPA × 7.1) + 11 — so read the band as an orientation, not as your figure.

Class boundaries are set per institution and the overlap in that last column is real, not evasion: distinction begins at 75% in most ordinances, at 70% in some and at 80% in a few. CGPA to percentage converts the figure on the formula you select and shows the substitution.

The only honest answer is that it depends on the filter in front of you, and the filters are public. Most mass campus recruiters set 6.0 or 6.5. Product companies and the better consulting firms commonly set 7.0 or 8.0. Public-sector recruitment and many postgraduate admissions work in percentage terms instead, which sends you back to the conversion problem.

Two things are worth knowing beyond the cut-off. A CGPA below 6.0 removes you from a large share of campus recruiting before anyone reads anything else, which is a structural problem rather than a judgement. And above roughly 8.5 the number stops differentiating — nearly every filter is already cleared, and what separates candidates is elsewhere.

The expansion of the acronym and the vocabulary around it — SPI, CPI, YGPA, OGPA — are covered in CGPA full form. For the single-semester figure, see what SGPA is, and for the difference between the two, SGPA vs CGPA.