Terms of service
- LimitLine is browser software for control charts, capability studies, statistical analysis and lean tools.
- Free is free. Pro and Student are one-time payments. Team and Expert monthly plans are planned and not on sale yet.
- Refunds: within 30 days of any payment, for any reason.
- LimitLine calculates statistics. You decide what to do with the results.
Who we are
LimitLine is operated by Nicholas Williford, doing business as LimitLine, Kernersville, North Carolina, United States. Contact: [email protected]. We answer within 2 business days.
What you get
- Free ($0): individuals (I-MR) charts with the Nelson rules, capability (Cp, Cpk, Pp, Ppk), Pareto and run charts, the chart picker, and 1 scan a day.
- Pro (one-time payment, currently $29) and Student (one-time payment, $15): every chart and analysis tool in the app, the Lean · TPS tools, exports, and 20 scans a day, for one person. Every 1.x update is included; your license keeps working even if a later major version is sold separately.
- Team and Expert (monthly plans): planned, not on sale yet. Their price and terms will be shown before you can buy, and these terms will be updated first.
Prices are shown in US dollars before tax. You receive a license key right after payment; it unlocks the features on your devices.
Payment
Purchases are processed by Stripe through Stripe Managed Payments. Stripe's Link acts as the reseller and merchant of record, so your card statement and receipt show "Sold through Link", and Stripe calculates and collects any sales tax or VAT. We never see or store your card number.
Refunds
If LimitLine isn't right for you, email [email protected] within 30 days of a payment and we'll refund that payment in full, for any reason. You can also ask Link support (support.link.com). Refunds go back to the original payment method. After a refund, the license key for that purchase stops working.
Cancelling a subscription
Cancel Team or Expert any time from the billing page linked in the app (License → Manage billing), or by emailing us. Cancellation takes effect at the end of the period you've paid for, and you keep access until then. We don't charge cancellation fees.
Your license
- A Pro or Student license is for one person; Team and Expert cover the number of users you pay for.
- Don't share, resell or publish license keys, or try to get around the license check.
- Student licenses are for one person who, when buying, is enrolled in a degree, diploma or certificate program at a recognised school, or is enrolled in a Lean Six Sigma or quality certification course or registered for a certification exam. Student licenses can be used for coursework, certification projects and work alike.
- To buy Student, confirm a school email address with a one-time code. If your school isn't recognised, or you're a certification candidate, email us proof of enrollment with ID numbers, photos and dates of birth covered; we delete it after deciding, usually within 2 business days.
- One Student license per person. To enforce this we keep a keyed one-way fingerprint of the school email, not the address itself.
- If a Student license was bought by someone who wasn't eligible, we may refund it, and its key then stops working. You're welcome to buy Pro instead.
Your data
On Free and Pro, your measurements stay in your browser; we can't see them. See the privacy policy for everything we collect and why.
Results and responsibility
LimitLine's calculations are tested against published reference data (for example NIST's worked examples), but software can have errors, and statistics depend on the data you enter and the method you choose. LimitLine calculates statistics; it does not certify a process, a product or a measurement system. Check important results before you rely on them for safety, regulatory, contractual or financial decisions.
Warranty and liability
Except for the refund promise above, LimitLine is provided "as is", without warranties of any kind, to the extent the law allows. To the extent the law allows, our total liability for any claim about LimitLine is limited to the amount you paid us in the 12 months before the claim, and we are not liable for indirect or consequential losses. Some places don't allow these limits, so they may not apply to you.
Acceptable use
Don't use LimitLine to break the law, to attack or overload the service, or to copy and resell the software.
Changes and law
We may update these terms; the effective date above will change, and if you have a paid license or subscription we'll email you before a change that affects you takes effect. These terms are governed by the laws of North Carolina, United States.