I'm a developer and would like to create a stock market replay tool. i.e. I'd like to be able to replay a particular day (or subset of a day) tick by tick to test my trading hypotheses. Oddly, the coding is the simple part. Finding accurate tick by tick data for a specific day is more difficult. Can anyone provide suggestions for a source of free tick-by-tick data? Thank you
There are no free reliable tick by tick data providers. The best data you will have access to for free is maybe 1 minute intervals.
-I was a professional trader for a few years.