Cookie Policy
Last updated October 6, 2026.
Analytics cookies (Google Analytics)
The public pages load Google Analytics, which sets these cookies so we can count visits and tell new visitors from returning ones:
| Cookie | Set by | Purpose | Lasts |
|---|---|---|---|
_ga |
Google Analytics | Tells one browser from another | 2 years |
_ga_<ID> |
Google Analytics | Keeps track of the current visit | 2 years |
We send Google only the path of each page, never the calculator inputs in the address. Google Signals and ad personalization are off. Analytics does not run on the sign-in, account or Kaight pages.
To opt out, block cookies for this site in your browser, use a content blocker, or install Google’s Analytics opt-out add-on. The site works the same without analytics.
Sign-in cookie
This site sets one cookie of its own, and only when you sign in (or start
signing in with Google). It is called session. It holds your account ID so
you stay signed in, and while you sign in with Google it briefly holds the
page to return you to. For the site’s own staff, it also holds a marker that
shows them the admin pages.
- It is signed, so it cannot be altered without detection.
- It is sent only over HTTPS and is not sent with requests other sites make to this one (SameSite=Lax).
- It lasts up to 14 days, or until you sign out.
The calculators’ last numbers (your browser’s storage)
When you run a calculator yourself, your browser keeps the numbers you ran in its local storage, one entry per
calculator (calc:retirement, calc:portfolio-review, calc:backtest), so the calculator can open on them next
time. They stay on this device: they are not a cookie, they are never sent to us, and we see your numbers only when
you open a result, in the page’s address, as before. Opening a link, whether someone shared it with you or it leads
into a calculator, keeps nothing, and neither does a page filled from My Plan or the worked example. Numbers you then
run yourself are kept, whatever they started from. Signing in brings you back to your numbers from this storage:
they never travel in the sign-in link.
- Clear under a calculator’s “Start from” forgets that calculator’s numbers.
- Signing out, or deleting your account, forgets them all.
- Clearing this site’s data in your browser forgets them all too.
- In a private window they last until the window closes.
We do not use advertising cookies.
See the privacy policy for what else we collect and who receives it.
Questions: [email protected].