Due to the lack of algorithm transparency, enterprises have started to proactively disclose algorithm information to attract consumers, but consumers are usually wary of the algorithms applied in their products, which affects the market acceptance of algorithm-controlled products. This paper argues that there is an interaction effect between algorithm adaptivity and brand letter case, and conducts one behavioral study and four laboratory studies to examine it. Specifically, Study 1a and Study 1b show that high-adaptivity (low-adaptivity) algorithm-controlled products with uppercase (lowercase) letter brand logos lead to higher purchase intention and APP download behavior. Study 2a reveals the mediating role of product performance expectations and further examines the impact of the interaction effect on willingness to pay. Study 2b demonstrates that products’ algorithm explanation moderates the interaction effect of algorithm adaptivity and brand letter case on usage intention. Study 3 illustrates the moderating role of letter spacing, where the interaction between algorithm adaptivity and brand letter case weakens consumers’ usage intention when the letter spacing was loose (vs. tight).