The psychology of online shopping, with the evidence attached.
Consumer Psychology Index is a free reference for people who build and run ecommerce sites, setting out what the research says about how people shop online and, the part most guides leave out, how sure anyone can be about it.
Most advice on this subject arrives without its sources.
Advice about ecommerce psychology is easy to find, and it usually arrives as a list of tactics, each presented as though it were equally proven. They aren’t. Some rest on decades of replicated research; some rest on one famous study that later failed to replicate; and some are useful ways of thinking that have never been tested on a shop at all.
Anyone deciding what to change on a site needs to know which is which, so each principle here names its research, links to it, and carries a rating that says how far the evidence goes.
Where the evidence is weak or disputed, the entry says so.
“We’ve never asked a client to take our word for it. We show them the research. Now that research is free for everyone, so the next change you make to your site can rest on evidence rather than gut feel.”
Consumer Psychology Index is built by Ostrich and Zebra, a growth consultancy that works with ecommerce brands. It’s free to use, with no account to create and nothing to sign up to.
Visit Ostrich and ZebraFive things, on every principle.
What it is and why it works, in plain language.
Where it belongs on an ecommerce site and what to do with it, including what to avoid.
The studies behind it, each linked to the published source so you can read it yourself.
One of four ratings, with a note explaining why the entry earned it.
How we rate evidenceWhere a tactic can mislead shoppers or fall foul of UK consumer law, the entry says so.
Three limits worth knowing.
Not a promise of results
A principle that held up in the research may still do nothing on your site, which is why each one is better treated as something to test than something to install.
Not legal advice
The notes on the law refer to UK consumer law and are there to point out risk; they don’t replace advice from a lawyer.
Not the final word
Ratings are editorial judgements of the research available to us at the time, and because research moves, a rating can change when it does.
Researched with AI, checked against the source.
Each of the principles was researched and drafted with the help of AI, allowing us to undertake research at scale. Each citation is then being checked against the published sources, which we link to for you to check yourself.
On occasions, mistakes may slip through and sources may be updated or refuted. When this happens, we seek to update our rating as promptly as possible. But if you spot a mistake, let us know and we’ll look into it.
Two ways to reach us.
Start with the 104 principles.
Browse them all, or narrow them by page area, kind of psychology or strength of evidence.
Browse the database