ABOUT

One entered dataset.
One transparent line.

Fitline is a free, focused browser calculator for checking one unweighted ordinary least-squares straight-line model with an intercept.

What it does

It calculates coefficients and residuals from the numeric rows you supply. Its exact-fraction arithmetic describes those entered decimals; it does not establish that a model fits a real process, improve measurement accuracy or infer future outcomes. The worked guide explains the scope and rejected states.

How it is operated

The calculator runs locally without a user account, upload or paid feature. This initial release has no active advertising, analytics or consent-message loader. Publisher metadata and ads.txt prepare the intended publisher identification; they are not proof of approval, advertisements or income. The privacy notice describes the prepared configuration.

Contact

This independently operated tool uses the existing shared Yardfill portfolio forwarding alias, not a separate Fitline mailbox. See the contact page for corrections or privacy enquiries. No contact is required to use the calculator.