Starting with first-year high school students in 2025, Korea's internal grading shifts from the 9-tier system to a 5-tier system. This major change applies from the 2028 college admissions cycle, when these students enter university. Here's what changes and why.
Why the change to 5 tiers?
Under the old 9-tier system, Tier 1 was limited to the top 4%, creating intense competition where a single question could change a grade. The government simplified grading to 5 tiers to ease this burden and strengthen achievement-based evaluation in line with the high school credit system.
- Who: First-year students from 2025 (born 2009)
- Admissions: From the 2028 cycle
- Current 2nd/3rd years: Remain on the 9-tier system
9-tier vs 5-tier comparison
The biggest change is that Tier 1 expands from the top 4% to the top 10%. The cumulative cutoffs simplify as follows.
| Tier | 5-tier (cumulative) | 9-tier (reference) |
|---|---|---|
| 1 | Top 10% | Top 4% |
| 2 | 10–34% | 4–11% |
| 3 | 34–66% | 11–23% |
| 4 | 66–90% | 23–40% |
| 5 | 90–100% | 40–60% |
Check your rank grade from your raw score, average, and standard deviation with the High School 5-Tier Grade Calculator.
Achievement levels (A–E) are recorded together
Another key point is that the rank grade (relative) and achievement level (absolute) are recorded together. For most subjects, both appear on the report card.
| Achievement | Raw score |
|---|---|
| A | 90+ |
| B | 80–90 |
| C | 70–80 |
| D | 60–70 |
| E | below 60 |
Even with a lower rank grade, securing a raw score of 90+ earns achievement level A, making absolute mastery more important than before.
Grade management strategy
- Aim for A (90+): Since achievement and rank grade appear together, reliably securing 90+ is advantageous.
- Prepare for lower differentiation: With a wider Tier 1, universities weigh detailed activity records and achievement levels more holistically.
- Don't forget the CSAT: Separately, check your CSAT/mock exam grade and college conversion score to balance early and regular admission strategies.
Check instantly with CalKit calculators
- High School 5-Tier Grade Calculator — rank grade + achievement level
- School Grade Calculator (9-tier) — for current 2nd/3rd years
- CSAT Grade Cutoff Calculator — standard score, percentile, grade
- College Admission Score Calculator — reflection-ratio weighting