The Definitive 2019 Guide to Cryptographic Key Sizes and Algorithm Recommendations
A lot has been written about cryptography key lengths from academics (e.g. Lenstra's equation) and various standard committees (ECRYPT-CSA, Germany's BSI, America's NIST, etc.) over the years.
Despite the abundance of coverage on this material on the Internet, these resources lack the clarity that we look for when drafting recommendations for software developers and system administrators. Additionally, many of them are showing their age and desperately need to be brought up to speed with a modern understanding of real-world cryptography.