# Can I judge liquid thickness by eye instead of testing?

Canonical: [https://followyourswallow.com/answers/why-cant-i-just-guess-the-thickness](https://followyourswallow.com/answers/why-cant-i-just-guess-the-thickness)

## Direct answer

No. Visual judgment is unreliable, even for professionals. The same product can test differently between batches, temperatures, and standing times. The 10 mL syringe flow test takes about two minutes and is the only way to know what level a batch actually is.

## Details

Levels 1 and 2 in particular are nearly impossible to distinguish by eye. The consequences of serving a too-thin liquid to someone who aspirates thin liquids can be serious: aspiration is often silent, with no cough at all.

Our guided flow test walks you through the official method with a timer and tells you what level your batch tested at.



Clinical review: SLP review in progress

## Safety

Use only the food and drink levels prescribed by the person's qualified clinician. Test the actual serving before it is eaten or drunk.