---
title: Astigmatism test
description: "An [astigmatism test](https://bluefinvision.com/astigmatism-test-online/) checks whether the cornea or lens has an irregular curve that causes blurred or distorted vision. Astigmatism is very common and can occur alongside short‑sightedness or long‑sightedness. ## Common methods Optometrists use a mix of charts and…"
url: "https://bluefinvision.com/knowledge-base/topics/diagnostics-testing/astigmatism-test/"
updated: "2026-01-22"
category: "Diagnostics & Testing"
---

# Astigmatism test

An [astigmatism test](https://bluefinvision.com/astigmatism-test-online/) checks whether the cornea or lens has an irregular curve that causes blurred or distorted vision. Astigmatism is very common and can occur alongside short‑sightedness or long‑sightedness.

## Common methods

Optometrists use a mix of charts and instruments.

- Refraction with a phoropter to find the best lens correction
- Special charts with radiating lines to see if some look clearer or darker
- Corneal topography or keratometry to measure the corneal shape
- Autorefractors to provide an initial estimate of astigmatic power and axis

## Why it is important

Correcting astigmatism can greatly sharpen vision.

- Reduces eyestrain, headaches, and ghosting of images
- Guides the choice of glasses, contact lenses, or laser vision correction
- Helps detect irregular astigmatism from keratoconus or previous surgery
- Should be checked regularly, especially if prescriptions are changing