Privacy policy
Last updated October 18, 2026
Fantasy Trade Hero is a free tool with no accounts. We don't ask for your name or email, and we don't sell or share personal information. This page explains the little data the site does handle.
What stays in your browser
These are saved in your browser's local storage so the site remembers them between visits. They aren't stored on our servers:
- Your league settings (format, teams, scoring, lineup slots, projection sources).
- A connected league's name, IDs and settings, and which team is yours.
- A roster you enter by hand.
- Your Sleeper username, so you don't have to retype it.
Clearing your browser's site data removes all of it.
Cookies
We use only cookies the site needs to work. There are no advertising or tracking cookies.
- Yahoo session (only if you connect Yahoo): your Yahoo access and refresh tokens, encrypted, so the site can load your leagues. It lasts up to 90 days and is deleted when you click Sign out of Yahoo.
- Yahoo sign-in check: a random value that protects the sign-in from forgery. It expires after 10 minutes.
- Access cookie: only while the site is in private beta, to remember that you entered the beta password.
Sleeper and Yahoo leagues
When you connect a Sleeper league, our server looks up your username and league on Sleeper's public API and caches the response for a few minutes. Sleeper league data is public; no password is involved.
When you connect Yahoo, you sign in on Yahoo's own site and grant read-only access to your fantasy sports data. Your Yahoo password never reaches us. We fetch your leagues and rosters only when you ask, use them to analyze trades in your browser, and don't store them on our servers. You can revoke access at any time in your Yahoo account's app permissions. Fantasy data provided by Yahoo Fantasy.
Logs and service providers
The site is hosted on Vercel, which keeps standard request logs (such as IP address, browser type and the page requested) for security and troubleshooting. To protect the site from abuse, we count recent requests per IP address in memory for about a minute. Player and projection data lives in a Supabase database, which holds no information about visitors.
We don't use third-party analytics today. If we add privacy-friendly, cookie-free analytics, we'll update this page.
Children
The site isn't directed to children under 13, and we don't knowingly collect information from them.
Changes and contact
If this policy changes, we'll update the date at the top. Questions? Email contact@fantasytradehero.com.