No. In fact there are limits but unless you've already written a 'perfect compression tool' you can't actually know the limit. https://en.wikipedia.org/wiki/Ko

No. In fact there are limits but unless you've already written a 'perfect compression tool' you can't actually know the limit. https://en.wikipedia.org/wiki/Kolmogorov_complexity https://en.wikipedia.org/wiki/Kolmogorov_complexity is ultimately what you're looking for btw. Shannon is more about limits in transmission speed given noise but Kolmogorov dealt with the limits of compression which is actually unknowable.