Background and Purpose: Vascular access site (VAS) bruising is common following invasive cardiac procedures. The extent of VAS bruising is underreported because of the lack of reliable measurement methods. This study examined the reliability of linear measurement and planimetry to measure VAS bruise size. Methods: There were 40 participants with VAS bruising after invasive cardiac procedures who completed VAS bruise measurement. Participants, a principal investigator, and a research assistant completed measurements independently. Inter-rater reliability was determined using intraclass correlation coefficient (ICC), 2-way random effects model. Results: The ICC for linear measurement and planimetry was high (.929 and .914 respectively). Both methods were reliable measures of VAS bruise size. Conclusions: Linear measurement or planimetry can be used with confidence to measure VAS bruising in clinical and research contexts.