Free calibration tools
Record the readings, work out the uncertainty, check the ratio and produce the certificate. Each tool works on its own, and what you enter in one carries over to the next.
Free, no login. What you enter stays in this browser.
- Step 1
As-found / as-left calibration sheet calculator
Enter range, tolerance and test points. Get the error and pass or fail for every point.
Open tool - Step 2
Measurement uncertainty budget calculator
List your uncertainty contributors. Get the combined and expanded uncertainty as a table.
Open tool - Step 3
Test uncertainty ratio (TUR) calculator
Enter the tolerance and your expanded uncertainty. Get the ratio and a check against 4:1.
Open tool - Step 4
Calibration certificate generator
Add lab, customer and reference standard details. Save the certificate as a PDF.
Open tool - Any time
ISO/IEC 17025 calibration certificate checklist
Tick what your certificate includes. Get the list of gaps against ISO/IEC 17025 clause 7.8.
Open tool
One calibration, four steps
A field calibration produces the readings, an uncertainty for them, a judgement about whether the measurement was good enough, and a certificate for the customer. These tools follow that order.
- Record the readings. The sheet calculates the error at every test point and marks each one pass or fail against your tolerance.
- Work out the uncertainty. The budget calculator combines your contributors into an expanded uncertainty.
- Check the uncertainty ratio. The calculator compares the tolerance with that uncertainty and tells you whether you reach 4:1.
- Issue the certificate. The generator puts the instrument, the reference standard, the results and the uncertainty on one page to save as a PDF.
The certificate checklist stands apart from the sequence. Use it on any certificate you already issue, to see what ISO/IEC 17025 clause 7.8 asks for that it does not show.
Everything is calculated in your browser. The tools use the same tolerance and decision-rule code as Probatus itself, so the result you see here is the result the full product would record.
Questions
- Are these tools really free?
- Yes. There is no account, no trial and no limit on how often you use them. They are made by Probatus, calibration management software for service companies, as a way to show how the full product handles the same work.
- Where is my data stored?
- In your own browser. Nothing you type is sent to a server, so the tools keep working with no signal once the page has loaded. Clearing the form, or clearing your browser data, removes it.
- Do I have to use the tools in order?
- No. Each one works on its own. Used in order, the sheet passes its tolerance on, the budget passes its expanded uncertainty to the ratio calculator, and everything ends up on the certificate, so nothing is typed twice.
Doing this for every instrument, every month?
Probatus is calibration management software for service companies: offline field sheets, master-standard traceability, approvals and signed PDF certificates in one place.