How to read urine glucose strips

How a reagent strip works

Urine glucose strips have a reactive pad that changes colour on contact with sugar: the more glucose present, the more the colour shifts (usually from blue-green towards brown). Comparing the colour with the reference scale gives an estimate of the amount.

The correct steps

Collect the urine in a clean container and dip the strip for the time stated on the pack.
Remove excess urine by tapping the edge, so it doesn't alter the result.
Wait the right time, usually about 30-60 seconds: reading too early or too late distorts the colour.
Compare with the scale in good light and read the matching value.

How to interpret the colour

The scale is semi-quantitative, often shown as plus signs or values: negative (no change), trace (~100 mg/dL), 1+ (~250), 2+ (~500), 3+ (~1000), 4+ (~2000 or more). The colour shows how much glucose is present, not the exact blood sugar. (Detail: what the values mean.)

The most common mistakes

Reading outside the stated time window.
Using expired or poorly stored strips (moisture ruins them).
Judging the colour in poor light or against a coloured background.

From colour to app

Reading the colour scale by eye is not always easy. Rima GlucoLens was built for exactly this: you run the test and the app reads the colour, reducing subjective error and explaining what the result means. (Guide: how to use the test.)

Frequently asked questions

How long should you wait to read the strip? Usually about 30-60 seconds: always follow the time stated on the pack.

Do you need to fast for a urine test? Usually no, unlike a blood draw; still follow the pack instructions.

Why can the colour be misleading? Poor light, wrong timing or damaged strips distort the colour: that is why reading with the app is more reliable.

Screening at home

Rima GlucoLens lets you run this screening simply and non-invasively, at home, and the app helps you read and interpret the result. It remains a screening tool: assessment and diagnosis always rest with a healthcare professional.

References: World Health Organization (WHO); American Diabetes Association (ADA); MSD Manuals. This article is for information only and does not replace medical advice.

Last updated: July 2026