Abstract: Some embodiments include methods and systems for performing non-deterministic load testing of a network-based production service. Some embodiments perform, using a load testing system implemented on one or more computers, receiving a load testing specification. The load testing specification indicates one or more load testing conditions for performing non-deterministic load testing of a network-based production service executing transactions in a networked computing environment. Some embodiments perform requesting from the virtual computing service resources to perform the non-deterministic load testing of the network-based production service, perform the non-deterministic load testing of the network-based production service. The non-deterministic load testing comprises executing test transactions on the network-based production service at pseudo-randomly varying times to measure system performance of the network-based production service at a plurality of levels of transaction intensity.