How the score
is calculated
No black boxes. Every point is traceable — here is the full formula, the same one that runs in our engine.
Every failed check becomes a weighted issue
Checks that fail are graded by severity. Each severity subtracts a fixed number of points from its category. Informational findings never cost you points.
Each category starts at 100 and loses its penalties
Within a category we sum the penalties of every issue (capped so a category never drops below 0) and subtract from a perfect 100.
categoryScore = max(0, 100 − Σ penalties)Categories combine by weight into one score
Not every category matters equally — performance and SEO move revenue more than a stray security header. Each category's score is multiplied by its weight, then summed and rounded.
overallScore = round( Σ categoryScore × weight )A worked example
Say Performance (20% weight) has one Critical issue (−30) and one Medium issue (−9). Its category score is 100 − 39 = 61. That contributes 61 × 0.20 = 12.2 points toward the overall score, out of a possible 20. Do that for all eight categories, sum, and round — that's your health score.
Frequently asked questions
What counts as a good score?+
Broadly: 90+ is excellent, 70–89 is solid with room to improve, 50–69 signals meaningful issues, and below 50 means several high-impact problems are dragging the store down. The per-category breakdown tells you where to focus first.
Why is Performance weighted the highest?+
At 20%, performance carries the most weight because page speed has the clearest, best-documented link to conversion and revenue on Shopify. SEO follows at 18% for similar reasons.
Do informational findings lower my score?+
No. Only Critical (−30), High (−18), Medium (−9) and Low (−4) issues subtract points. Info-level findings are context and never affect the score.
Can a category score go negative?+
No. Penalties within a category are capped so the category score never drops below 0, and the weighted overall score always lands between 0 and 100.