Aim. To address the scarcity of high–quality experimental benchmarks in metagenomics by developing a cost–effective, semi–real benchmark generation tool, MetaWiz, which can modify existing experimental data to create diverse and realistic metagenomic benchmarks. Conclusions. MetaWiz offers a cost–effective solution to the challenge of generating high–quality benchmarks in metagenomics. The tool's ability to create semi–real benchmarks from existing experimental data maintains crucial technological and biological aspects, providing advantages over purely computational simulations. This approach can be extended beyond viral sequences to various sequencing data, enhancing the comprehensiveness of metagenomics benchmarking studies across different biological contexts.