Which PP number are you looking at?
Star rating is calculated difficulty, not a prediction of your result. Score PP evaluates a particular performance; profile PP combines weighted performances. Keep those three numbers separate. A calculator's SS scenario assumes a perfect result and is not a personal target by itself. Before comparing two estimates, check the exact difficulty, ruleset, mods and rate, then ask whether the assumed accuracy and misses resemble your recent complete attempts.
Why a 200 PP play does not add 200 PP
The weight for a score at position n in your best performances is 0.95^(n-1). A 200 PP score in second place contributes 190 weighted PP. That contribution is not the profile increase: inserting it can move other scores down, and a replacement changes an existing contribution. Bonus PP is separate. For a useful before-and-after comparison, record your profile total and the score's position instead of subtracting its raw PP from your new total.
Build a realistic scenario before choosing a target
Suggested comparison: take three recent complete attempts on one difficulty and note accuracy, misses and slider breaks. Calculate a scenario resembling the middle attempt, another resembling your best repeatable attempt, and SS. Keep the same calculator and settings. If only the SS number looks attractive while actual attempts repeatedly fail the ending, move that map into practice rather than treating its ceiling as expected earnings. Do not estimate PP by multiplying SS PP by accuracy or a compatibility percentage.
Why do two calculators disagree?
Check the difficulty ID and whether one tool used an edited beatmap. Next compare mod settings, clock rate, judgement assumptions and calculation version. Official difficulty and PP updates can change old values. Record whether a number is an official submitted result or an estimate. If a tool lacks the necessary score data, leave PP unavailable rather than substituting zero or copying the value from another play on the same map.
Use PP without letting it choose every session
Try two similarly rated difficulties with different patterns. Use the one you can already execute consistently for a score attempt; use a specific troublesome section from the other for practice. Revisit both after several sessions under the same settings. Better accuracy or fewer repeat errors can justify continuing the exercise even before a new top score appears. There is no universal star-to-PP conversion or guaranteed daily profile gain.
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