Privacy Policy

Knuckleball LLC · Effective October 29, 2026 · Version 2026-10-29

Knuckleball is a pitch-charting app for baseball and softball pitchers and their coaches. It is run by Knuckleball LLC (“we”). This page explains what we store, who can see it, where it lives, and how to have it exported or deleted. Questions: nate@knuckleballonline.com.

What we collect

Account details: name, email address, password (handled by our sign-in provider; we never see it), and your sport and role (pitcher, coach, or parent).
Age bracket: whether you told us you're 18 or older, or 13 to 17, and when. We never ask for or store a date of birth. For 13–17 players: a parent or guardian's email address and whether they approved.
Players added by a parent: the player's name, sport, and throwing hand, plus the parent's consent and when it was given. We store no email address, login, or age for a player added this way — unless the parent gives a player who is 13 to 17 their own sign-in: then we also store that sign-in's email address and that the player is 13 to 17.
Linked sign-ins: who the parent who added a player has linked to that player (a second parent or guardian, the player's own sign-in, or friends and family), and when.
Player details: jersey number, throwing hand, pitch types, whether you use a radar gun, an optional profile photo, and up to three email addresses that reports can be sent to.
Charting data: every pitch charted — pitch type, target and location, velocity, result, delivery, time to plate — plus, for live games, counts, outs, runners and plays; session dates; and who charted each session.
Coach notes written on a session.
Chat messages at a training facility: what you write, who wrote it and when, including messages you delete, pinned messages and messages someone reported.
Team details: team names, rosters, coaching staff, level of play, and invite links.

Who can see it

You see everything in your own account, including any players you've added.
People a parent links to a player. The parent who added a player can give a one-time link to a second parent or guardian, to the player (13 to 17) for their own sign-in, and to up to five friends and family. A second parent or guardian and the player's own sign-in see everything about the player, can chart for them, and can chat with the player's coach at a training facility. Friends and family see the player's charting history only — sessions, their reports and coach notes — with no chat, contact details or charting. The parent who added the player can remove anyone at any time, and anyone linked can leave.
Your coaches — the head and assistant coaches of any team you're on — see your player details and the sessions you've charted since you joined their team — including sessions charted for your other teams — with their notes. Only the team a session was charted for can add notes to it, create or send its report, or delete it. If you leave a team, its coaches keep the sessions charted for that team while you were on it, but stop seeing anything else; coaches of an archived team stop seeing your new sessions too. For a player added by a parent, they also see that the player is on a parent account.
Teammates on a baseball team see the team leaderboard, which shows rankings (peak velocity, accuracy, strike percentage) and pitch counts — never anyone's sessions, pitch charts, or notes. Softball has no leaderboard.
Teams, organizations and analytics partners that license Knuckleball data. We may license charting data and the statistics built from it to other parties, as described in “How we may use and license charting data” below.
Anyone with a report link. A session report lives at a long, random web address. Anyone who has that link can view the report, and the report page also shows that session's current coach notes. Reports go only to the addresses on your account, but a link can be forwarded — treat it like a shared document.

At a training facility

The facility manager runs the facility. They see every pitcher at the facility, their player details and the sessions charted there, and can move pitchers between pitching coaches.
Each pitching coach at the facility sees only the pitchers they coach there.
Coaches of your other teams also see sessions charted at the facility (lessons), the same way they see sessions charted for any of your teams.
Chat. A private chat is between a pitcher's coach at the facility and the pitcher — or, for a player added by a parent, that parent, a second parent or guardian they linked, and the player's own sign-in. Messages to everyone at the facility come only from the facility manager. The facility manager can read every chat at the facility, including closed chats and the text of deleted messages. Coaches of your other teams never see facility chats.

Inside the app, these limits are enforced by the database itself (see “Data handling commitments” below), not just by the app's screens.

How we may use and license charting data

By using Knuckleball, players, parents and teams agree that Knuckleball LLC may use the charting data saved in the app, and the statistics built from it, for its own purposes, including licensing or selling it to other parties for a fee. We don't do this today, and we may never do it, but these terms keep that option open.

What may be shared: charting data and statistics (for example pitch types, locations, velocity, strike percentage, accuracy, pitch counts, results, spray charts and trends), together with the player's name, team, sport, level, jersey number and throwing hand, so that the numbers can be attributed to a player.
Who it may go to: teams, programs, organizations, scouts and analytics companies. If we offer it, we'll offer it on the same terms to any team or organization willing to pay for it, not to one team and not another.
What we never sell or license: email addresses (yours, a guardian's, or report contacts), passwords, age brackets, consent records, profile photos, and coach notes.
Players added by a parent (including every player under 13): their data is never licensed unless the parent separately agrees to it when we ask.
When it applies: to charting data saved on or after October 17, 2026.
Deleting: sessions and accounts you delete are left out of anything we license after the deletion. Data already licensed before a deletion can't be recalled.

Where it lives

Supabase stores the database, sign-in, and report pages, in its US East (N. Virginia) region. Supabase states: “All customer data is encrypted at rest with AES-256 and in transit via TLS.” (supabase.com/security)
GitHub Pages serves the website itself.
Cloudflare provides our domain's DNS and email routing.
Resend sends our emails (account verification, reports, guardian approval requests, and roster notices).

We use no other service providers.

No tracking, advertising, or analytics

Knuckleball has no advertising, no analytics, and no third-party tracking of any kind. Our web pages load only files from knuckleballonline.com itself (including our fonts) and talk only to our Supabase database. To work without a connection, the app keeps your sign-in and any not-yet-synced sessions in your browser's own storage; we don't use tracking cookies, so there's nothing for a cookie banner to ask about.

Age and children

You must be 13 or older to create your own account.
If you're 13 to 17, a parent or guardian must approve your account by an emailed link. Until they do, you can chart, but you can't view or send reports.
A parent or legal guardian can create a parent account and add their child as a player, at any age, including under 13. The parent holds the account and its login, gives consent when adding the player, and receives the player's reports. The child gets no email address or login of their own, unless the parent gives a player who is 13 to 17 a sign-in link: that sign-in is approved by the parent, and the parent can remove it. A player under 13 never gets a sign-in.
Players under 13 can use Knuckleball only through a parent account.
Coaches and parents must be 18 or older.

If we learn that someone under 13 has created their own account, or that a player's age was given incorrectly, we'll contact the account's email and delete the account and its data.

Keeping and deleting data

Saved sessions are final: pitch data can't be edited after a session is saved.
A pitcher can delete their own sessions, and a head coach can delete their team's. A deleted session's pitches are removed, and a marker stays in history showing the date, the number of pitches, and who deleted it.
You can download a copy of your data at any time, in the app: Profile → Your data → Download my data.
You can delete your account in the app: Profile → Your data → Delete my account. Nothing is deleted for 7 days; sign in before then and choose Restore my account to cancel. After 7 days we delete your login and every profile on it, including players you added; the sessions you pitched, with their pitches, notes and reports (each leaves only a dated record of how many pitches were thrown, which can't be opened); the notes you wrote; and your team memberships, report contacts and consent records. Sessions you charted for other pitchers stay with those pitchers, shown as charted by “Former coach.” We email you when the deletion is scheduled and again when it's done — and your parent or guardian too, if they approved your account. A head coach hands off or archives their teams first.
A parent can delete a player they added the same way, from that player's profile.
Linked sign-ins: a linked person's access ends when the parent who added the player removes them, when they leave, or when the player or their own account is deleted. Download my data lists who can see the players you added, and the players you can see.
Chat: a deleted message shows as deleted to everyone; its text is kept for the facility manager until the chat is cleared. A coach can close a chat: it becomes read only, and the facility manager can read it for 90 days, after which it is deleted automatically. A chat also closes when the pitcher stops training with that coach. When you delete your account, the text of your messages is removed and they show as from a “Deleted account”. Download my data includes the chat messages you wrote.
Copies in our backups are removed within 7 days of a deletion.
If you can't sign in, email nate@knuckleballonline.com from your account's email address and we'll help within 30 days.

Data handling commitments

For coaches and programs evaluating Knuckleball:

(a) Team-scoped access is enforced in the database

Who can read which rows is enforced by row-level security policies in the database, not only by the app's code. For example, inside the app a session is readable by its pitcher and by the coaches of the team it was charted under, and by no other user. Secret values such as invite links and approval codes can't be read directly at all; they're reachable only through purpose-built server functions.

(b) Licensing charting data

Knuckleball LLC may license or sell charting data and the statistics built from it, as described in “How we may use and license charting data” above. We never sell or license email addresses, passwords, age brackets, consent records, profile photos, or coach notes.

(c) No tracking, advertising, or analytics code

None is included anywhere in the app or its pages; the only outside service our pages talk to is our Supabase database.

(d) Encryption

Data is stored with Supabase, which states that “all customer data is encrypted at rest with AES-256 and in transit via TLS.”

(e) Who at Knuckleball can access data

Knuckleball is run by a small team. As the operators of the service, we can technically access the data it stores, as with any hosted service. We access it for support, debugging, safety, and the uses described in “How we may use and license charting data” above.

(f) Export and deletion

In the app, from Profile → Your data: download a copy at any time, or delete an account with 7 days to restore it; backups are cleared within 7 days of a deletion. Or by email to nate@knuckleballonline.com, answered within 30 days.

Changes

If we change this policy, we'll update this page and its version and effective date, and tell account holders by email or in the app when the change matters to them.