In this article, four different structural epoxy adhesives such as SPABOND (TM) 820HTA (non-toughened), SPABOND (TM) 840HTA (toughened) adhesives, and their two hybrid combinations are fabricated using a manual mixing method. Quasi-static tensile experiments are conducted at standardized and high strain rates using ASTM D638-22 Type II specimens to investigate the strain rate effects on the tensile properties. Tensile-tensile fatigue experiments are performed using ASTM D638-22 Type I and Type II specimens to evaluate the impact of specimen geometry and toughening on fatigue life. The digital image correlation technique is utilized to obtain full-field strain data in these experiments. Technical data analysis, plotting, smoothing, filtering, and averaging are carried out using Origin Pro((R)) and MATLAB R2021b((R)). The obtained S-N curve data can be used to develop fatigue failure criteria and predict the behavior of wind turbine blade adhesive joints through finite element modeling. (c) 2023 The Author(s). Published by Elsevier Inc.