DatumLab Premium
The measuring surface of this site is the free product: every calculator, the tolerance zone plot, the feature control frame tools and the reference pages, forever. Premium is for the study side, the volume of questions and the record of what you have mastered.
What Premium adds
- Unlimited practice on every topic, not only the four free ones
- Weak area targeting across every characteristic
- Timed exam simulation, twenty five items against the clock
- Unlimited saved cases, past the free 5
- A printable inspection style case sheet
Weekly, yearly and lifetime plans are available.
Free forever
- Every calculator and the position plot
- The feature control frame composer and reader
- Every guide and reference page, with no item hidden from a crawler
- Unlimited practice on four full topics
- Mastery tracking and the mistakes notebook
- JSON export and import of your saved cases
Everything is currently free
Premium plans are not on sale yet, so every feature above, the timed sessions included, is open to everyone. Nothing to buy, nothing locked. DatumLab will never move a free calculator behind a payment.
Frequently asked questions
What stays free?
Every calculator, the tolerance zone plot, the feature control frame composer and reader, every guide and reference page, JSON export and import of your saved cases, and 10 practice questions a day with the full reasoning written out. No account is needed and nothing you enter leaves your browser.
What does Premium add?
The study conveniences: the full authored question bank across every geometric characteristic, mastery tracking and spaced repetition by characteristic and difficulty, timed mock sessions in a certification style, and unlimited saved cases with a printable inspection style case sheet. The free tier keeps 5 saved cases.
Are the numbers different in Premium?
No. Every formula, every verdict and every figure is identical for everyone, and all of it follows ASME Y14.5-2018. Premium removes a volume cap and adds the timer and the progress record. It hides no calculation and changes no result.
How is my access stored?
Purchases are handled by RevenueCat and Stripe. An anonymous purchase id is kept in this browser so DatumLab recognises your Premium on this device. Keep your receipt email for recovery.
I already subscribed on another browser or device, how do I get Premium here?
Open the restore page and paste the access code shown on this Premium page, or the one from your receipt. Premium moves to this browser instantly.
Can I cancel?
Yes. Subscriptions renew automatically and can be cancelled anytime from the link in your receipt email. Lifetime is a one-time payment.
Lost your access code?
Your code is shown on this page whenever you are subscribed here, and it is in your purchase receipt email. If you cannot find it, reply to your receipt email from the address you paid with. Your subscription is tied to it and access can be recovered from there.