went through the Workday online assessment and coding rounds last month. posting format info because the threads i found were all 2-3 years old and things have shifted.
online assessment (OA): HackerRank based. 2 coding problems, 90 minutes. difficulty was medium-ish. one was a string/array manipulation problem (nothing tricky algorithmically, O(n) solution), the second involved processing a nested data structure that felt vaguely payroll-ish in theme. passing/failing test cases but no visible expected output. finished in about 50 minutes.
also a short behavioral / situational section tacked on at the end, maybe 15 multiple choice questions. the kind where every answer seems reasonable and you have to pick the most 'enterprise values' one. i just went with 'what would a cautious, process-following person do' and seemed fine.
coding in the onsite: mine was on Workday's internal coding tool, screen shared. two problems back to back, 60 minutes total. one definitely leetcode medium, one felt like a medium leaning toward hard (recursive tree problem). they were okay with me thinking out loud and didn't rush me. no trick questions or trick inputs but they did ask me to optimize after my first solution on the harder one.
there's also usually a coding round framed around 'design a small class/API' not just solve-a-problem. think: implement a simplified time-off request system with basic rules. tests the same DSA but grounded in realistic scenarios.
level of prep needed: honestly you could over-prepare for Workday's coding rounds. solid mediums, clean code, talk through your approach. they're not google or meta on algo difficulty. if you can solve blind 75, you're probably fine.