The Skolkoll score is a composite index between 0 and 100 combining five dimensions. It gives an overview of available statistics, but is not a complete assessment of school quality. Read the dimensions and data coverage alongside the total.
The five dimensions
| Dimension | Weight | Source | What it measures |
|---|---|---|---|
| Results | 30 % | Skolverket | The percentile of the first available result metric: Year 9 final-grade score, upper-secondary average grade points, Year 9 upper-secondary eligibility, graduation within three years or higher-education eligibility, in that order. |
| Staff | 25 % | Skolverket | Percentile rank for the share of certified teachers in the school's comparison group. |
| Value-added | 20 % | SALSA/Skolverket | The gap between actual and expected final-grade score (SALSA residual) for compulsory schools. The residual is clamped to −60 through +60 and mapped linearly: −60 gives 0, 0 gives 50 and +60 gives 100, rounded to a whole number. |
| Safety | 15 % | Schools survey | Safety index (0–100) computed from safety, study calm, anti-bullying and staff assessment. |
| Resources | 10 % | Skolverket | Teacher density (pupils per teacher) percentile rank. Lower ratio = higher score. |
How the calculation works
- Results, staff and resources use percentiles among active school units of the same type (compulsory or upper-secondary) with data for the particular metric. Each school unit has equal weight, regardless of pupil count. The percentile counts the share of values below the school's value plus half the share of equal values, rounded to a whole number. For pupils per teacher, the scale is reversed so a lower ratio gives a higher score.
- Value-added uses the SALSA mapping above. Safety uses the safety index directly. These two dimensions are not percentile-ranked.
- The five weights are fixed: 30%, 25%, 20%, 15% and 10%. A dimension without usable school-specific data receives the neutral value 50, with the same weight. Weights are not redistributed.
- The weighted dimension values are added, clamped to 0–100 and rounded to a whole number.
Example: results 80, staff 60, missing value-added (50), safety 70 and resources 40 give 80 × 0.30 + 60 × 0.25 + 50 × 0.20 + 70 × 0.15 + 40 × 0.10 = 63.5 → 64. The missing value-added dimension therefore keeps its 20% weight.
How to interpret the index
The total is not a percentile rank: 64 does not mean the school ranks above 64% of schools. 50 is the scale midpoint and a neutral replacement value, not a measured national average or national median for the composite index. A higher total means a higher weighted index, but does not by itself show how many dimensions are above average.
Data coverage and pupil sample
The number of dimensions with school-specific data is shown alongside the score. In the school overview, data coverage is high with at least 4 such dimensions, medium with 2–3 and low with fewer than 2. A limited pupil sample caps the level at medium. With fewer than 10 pupils the score is hidden and coverage is labelled low; with 10–24 pupils a limited-sample warning is shown. An unknown pupil count does not trigger these pupil-count thresholds. Fewer available dimensions mean more neutral replacement values in the index.
Transparency
All weights and computations are open. Each school page shows the individual dimension values alongside the total. Source data comes from Skolverket, SCB and the Swedish Schools Inspectorate's survey. No paying customer can influence how the score is calculated.
When data is missing (fallback)
Whenever a score can be calculated, it includes 5 dimensions. Missing dimensions receive the neutral replacement value 50, including, for example, value-added for upper-secondary schools. A SALSA value that does not meet the sample requirements is also left unused. If both results and staff data are missing, no score is calculated, even when other dimensions have data. Missing data must not be read as a measured average result.
Common reasons for missing data and what can be done about them:
- Value-added (SALSA): Only compulsory schools with Year 9 and a sufficient pupil base receive SALSA values. Skolverket publishes SALSA each February. If a school is missing SALSA, verify that grade statistics are correctly reported to SIRIS.
- Safety: Requires the school to take part in the Schools Inspectorate survey (Skolenkäten). Contact Skolinspektionen if the school is not receiving the survey.
- Results: Published via Skolverket's statistics database. Ensure the school's results data is reported on time.
- Staff/Resources: Sourced from Skolverket's personnel and cost statistics. Ensure the school unit is correctly registered in the School Unit Register.