HACKER Q&A
📣 tndibona

Track Users Without Fingerprinting


I want to be able to give users a 3 day trial period to use my product (a React + Node.js web app) without a sign-up. Seems that the best option online is fingerprint.com and I've learned the hard way that the free npm version is only 60% accurate.

My other option is to save a uuid on the browser's local storage to track the user. This wont work if the user erased their history.

I'd like to pause and ask the community - Is there a fundamentally better way to do an x-day free trial?


  👤 mtmail Accepted Answer ✓
We do signup, including captcha, email confirmation step, record IP addresses, extensive check against temporary/burner/disposable email addresses. Still 10 people per day sign up multiple times. If people want to go over the trial period they will. Literally while I was writing this I got a notification of a repeat signup and sure enough the user hit their quota and just signed up with another email address to continue. That's the reason you see websites requiring phone number or credit card verification these days.

👤 yjftsjthsd-h
Is it really worth the effort to do more than email and maybe IP? It's not perfect, but nothing is, so you might as well not burn too much time/money/code on it.

👤 dangus
In my opinion, step back and consider what your goal is before rushing to constraints.

Is your goal to have low friction trials without abuse? A admirable goal, but why no sign ups?

I think I would want prospective customers to sign up. Someone who isn’t even enthusiastic enough about my product to give an email address probably won’t want to convert anyway.

Those “annoying” marketing emails you get when you sign up for free trials? They work. That’s what you should be doing.

If you have people sign up you can also contact them for feedback. Why did they decide to convert to paid? Why did they decide against your solution? If you can get feedback like that from real prospects, that’s gold. I can’t willfully giving up the chance to receive that feedback by keeping my trial users anonymous.


👤 axelthegerman
Even with sign up there are ways to get around it by creating multiple accounts, so good luck getting even close without sign up AND without fingerprinting.

At the same time you might get more false positives the harder you try, e.g. IP addresses can be legitimately shared between users while the ones trying to get around your limits know how to change theirs


👤 quickthrower2
You could do a simple email link passwordless sign in

I think if you tie this to browser state it is too easy to keep renewing.

Even with emails it is easy but trickier for most people unless they own a domain or use plus addresses.