The aim of this study is to investigate consumer responses to emerging digital fit and sizing tools in online fashion retailing. Digital fit and sizing tools are assumed to reduce returns, increase sales conversions (Dacko 2016) and bridge physical and digital assessment in online retailing contexts (Pantano and Timmermans 2016, Roy et al. 2016). However little is undestood regarding their impact on consumer behaviour. Research is required to gain a holistic understanding of how the tools aid consumer decisions and to deduce whether they can assist with key retailer metrics. This research is split into three stages: stage 1 which investigates the responses of 400 females aged 18-24 to pre-purchase virtual fit website Metail.com. Stage 2 explores the garment fit evaluation of 20 females, aged 18-34 to physical garments purchased using size and style recommender tools on Very.co.uk or Topshop.com. Stage 3 explores the opinions of 6 industry experts from top UK online fashion retailers through semi-structured interviews. Existing research in digital fit and sizing technology has been approached by garment technologists (Kim and LaBat 2012, Song and Ashdown 2015) or experiential marketers (Pantano and Servidio 2012, Beck and Crie 2016). This research aims to provide cohesion between the distinct areas of approach. The study reviews existing literature on experiential fashion technology, consumer behaviour and garment fit and sizing, and makes links between the approaches of each discipline. The research follows the consumer shopping journey framework proposed by Lemon and Verhoef (2016). Existing studies have often not captured consumer responses beyond online purchase intention (Huang and Liao 2015, Kim et al. 2016), and the shopping journey model recognises the importance of consumer experience pre and post-purchase. In addition, consumer fit evaluation is under-explored in extant research (Kasambala et al. 2016, deKlerk and Tselepis 2007). The study adopts the Technology Acceptance Model (TAM) (Davis 1989) to theoretically underpin the conclusive research on pre-purchase consumer evaluations using Metail. The TAM has been used in extant virtual fit or augmented reality fashion research (Perry 2016, Huang and Liao 2015). However, this study builds from existing research and extends the TAM to include the user trait: technology confidence and the experiential state: playfulness. The constructs measured in the post-purchase fit evaluation were derived through existing consumer behaviour research and the evaluation of garment fit and sizing (Kasambala et al. 2016, Eckman et al. 1990, McKinney and Shin 2016). Results of the study provide a guide to understanding the end-to-end processes behind consumer use of fit and sizing tools. The results of the research are conclusive (stage 1) and exploratory (stage 2 and 3) and were triangulated in the discussion to validate each approach.