About this converter — sources, method, limitations

Last updated 2026-08-24

What it does

The converter maps a score between the Korean 4.5 and 4.3 scales, the 100-point percentage scale, and the US 4.0 scale. It runs entirely in your browser: there is no account, no server call, and nothing you type leaves the page except through a share link you create yourself.

The three methods

• Proportional — score ÷ source max × target max. Simple, widely used, and blind to the different spacing of the A band.
• Band mapping — piecewise interpolation between letter-grade anchors (A+, A0, B+, …), so a Korean B+ maps to an American B+ rather than to a fraction of the scale.
• GKS table — the conversion table published in the Global Korea Scholarship guidelines, at 0.05 grade points per percentage point across the 60–100 range.

Known limitations

• A single cumulative number cannot reproduce a course-by-course evaluation such as WES iGPA.
• Universities that award A+, A, A- separately, or that use non-standard scales, are not modelled.
• The US 4.0 scale has no value above 4.0, so Korean A+ and A0 converge there.
• Band mapping returns the lower bound of a grade band when converting back to percentages.
• GKS guidelines are revised annually; verify against the current announcement.

Privacy

Inputs stay in your browser (localStorage) and in the optional share link. No sign-up, no tracking cookies beyond the analytics and advertising needed to keep the site online.