That depends on how inefficient the original compressor was. Rafał M's experience of 1-15% sounds about right, but if the png is the output of another compressor (eg. pngquant) then expect less than 1%, if any.
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dont really know, but I tried to compress few png's and I get something between 1%-15%
That depends on how inefficient the original compressor was. Rafał M's experience of 1-15% sounds about right, but if the png is the output of another compressor (eg. pngquant) then expect less than 1%, if any.