This policy explains how StackFloss, Inc. ("StackFloss," "we," "us") uses cookies and similar technologies on stackfloss.com (the "Site"), and how you can control them. It works alongside our Privacy Policy.
The short version. Analytics (Google Analytics) and advertising (Meta) are on unless you turn them off. We honor Global Privacy Control. You can change your choices anytime from Your Privacy Choices at the bottom of every page.
What these technologies are
Cookies are small text files a website stores in your browser. First-party cookies are set by us; third-party cookies are set by another company's service running on our Site. We also use local storage, browser storage that works like a cookie, and pixels, small pieces of code that tell a provider that a page was viewed or a form was submitted. This policy calls all of these "cookies."
How you choose
On your first visit, we show a short notice. Analytics and advertising are on unless you turn them off. Select Choices in the notice, or Your Privacy Choices at the bottom of any page, to turn either one off or back on. You'll see a toggle for each category.
We save your choice in a first-party cookie called sf_consent for 12 months. If you opt out, we won't ask you to opt back in for at least 12 months unless you open your choices yourself. Your choice is stored per browser and device.
Turning a category off stops those tools going forward and removes the cookies they set on our Site. It doesn't undo data collected before, but you can ask us to delete it (see our Privacy Policy).
What we use and why
Strictly necessary (always on)
These remember your privacy choices and simple things you've done on the Site, like closing an announcement. They don't track you. Because the Site needs them to respect your choices, they can't be turned off here, though you can block them in your browser.
Analytics (on unless you turn it off)
Google Analytics, loaded through Google Tag Manager, tells us how many people visit, which pages and forms they use, how they found us, and roughly where they are (city or region, from IP address). We use it in aggregate to improve the Site.
Advertising (on unless you turn it off, or your browser sends GPC)
The Meta Pixel lets Meta measure whether our Facebook and Instagram ads work (for example, whether someone who clicked an ad later signed up) and show StackFloss ads to people who may be interested. Meta may combine this with other information it holds about you. When advertising is on and you submit a form, our server also sends Meta a sign-up event with your email address in hashed form, so the sign-up can be matched to the ad that led to it. Under some state laws, this is "sharing" or "targeted advertising."
Cookie list
| Name | Provider | Category | Purpose | Duration |
|---|---|---|---|---|
sf_consent | StackFloss | Necessary | Stores your privacy choices and a random choice ID | 12 months |
sf_waitlist, sf_waitlist_banner (local storage) | StackFloss | Necessary | Remembers that you closed or completed the founding practice announcement, so we don't show it again | Until you clear it |
sf-bill (local storage) | StackFloss | Necessary | Remembers whether you chose monthly or annual prices | Until you clear it |
_ga | Google Analytics | Analytics | Distinguishes visitors | 2 years |
_ga_43FFG6FT47 | Google Analytics | Analytics | Keeps session state | 2 years |
_fbp | Meta | Advertising | Identifies your browser to Meta to measure and target ads | 90 days |
_fbc | Meta | Advertising | Stores the click ID when you arrive from a Meta ad | 90 days |
lastExternalReferrer, lastExternalReferrerTime (local storage) | Meta | Advertising | Set by the Meta Pixel to remember which outside site sent you here, and when | Until you clear it |
Providers change their cookies from time to time; this list reflects our current setup. Each provider's own privacy policy explains how it handles data: Google and Meta.
Our Site's fonts and images are served from our own domain, so loading a page doesn't send your information to a font or image provider.
Sale, sharing, and targeted ads
We don't sell personal information for money. But while advertising is on, Meta receives identifiers such as cookie IDs, IP address, and hashed email (when you submit a form), and information about your activity on our Site. Under the California Consumer Privacy Act and similar state laws, that can be considered a "sale," "sharing" for cross-context behavioral advertising, or "targeted advertising." To opt out, select Your Privacy Choices at the bottom of any page and turn advertising off, or turn on Global Privacy Control in your browser.
Global Privacy Control and Do Not Track
Global Privacy Control (GPC) is a browser setting that tells websites you want to opt out of sale, sharing, and targeted advertising. When we detect it, advertising stays off for that browser and can't be turned on, and our privacy choices panel shows "Opt-out preference signal honored." Learn more at globalprivacycontrol.org.
Do Not Track is an older signal with no agreed standard. We don't respond to it, but we honor GPC.
Other ways to control cookies
- Browser settings let you block or delete cookies and local storage. If you block
sf_consent, we can't remember your choices and will show the notice again. - Google Analytics offers an opt-out browser add-on.
- Meta lets you manage the ads you see in your ad preferences.
The StackFloss product
We don't use analytics or advertising tools inside the StackFloss product or on any page that handles patient information. This policy covers the public Site only.
Changes and contact
We'll update this policy when our tools change and revise the date below. If we add a new kind of tool, we'll show the notice again. Questions: hello@stackfloss.com.
Last updated: October 5, 2026.