demo · v134 · privacy-sandbox

Noise Padding Visualizer

Dial how many real contributions you make and what cap your worklet sets. See the resulting aggregatable report layout: real contributions in blue, noise padding in grey, dropped overflow in red. Pre-v134 every report was 20 slots; v134 lets callers choose.

8 20

pre-v134 report layout (always 20 slots):

v134 report layout (contributionLimit = 20):

real contribution noise padding (privacy) dropped overflow
20
report bytes (v134)
12
padding slots
0
dropped overflow

caller code (v134)


  


  

    
why this is two-sided

    
Two complaints landed on the spec:

    
    
      
  1. "20 isn't enough" — a fraud-detection or attribution worklet that wants 50+ buckets per report used to have to split work across multiple shared-storage operations.
    2. 
      
  2. "20 is wasteful" — a simple reach-measurement worklet that contributes only 1 bucket still paid the noise-padding cost of 20 slots, inflating network and aggregation-service compute.
    3. 
    

    
v134 lets the worklet pick. A modest cap = small report, small padding. A generous cap = no overflow, but bigger reports.

  


  

    
see also