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Visual Acuity conversion

MAR values to LogMAR values Converter

Convert MAR values to logMAR values using logMAR = log10(MAR). The formula is logMAR = log10(MAR); 1 MAR is 0 logMAR.

Base answer
1 MAR = 0 logMAR
Rounding
3 decimals
Formula type
Scale + offset
Conversion snapshot
From
MAR values (MAR)

Minimum angle of resolution, the reciprocal of decimal visual acuity.

To
LogMAR values (logMAR)

The base-10 logarithm of MAR, often used in vision research and chart scoring.

Live converter
MAR values to LogMAR values
Type a value in MAR values. The result updates in your browser, with no sign-in or external API.
Formula
logMAR = log10(MAR)
MAR
Converted value
0
logMAR (LogMAR values)
Common inputs:
How to convert MAR values to logMAR values
Visual acuity conversions compare Snellen, decimal acuity, MAR, and logMAR notation used in chart references and research.

Start with your value in MAR values, then apply the formula below. It stays visible so you can catch rounding mistakes instead of just copying the output.

Formula
logMAR = log10(MAR)

Use these values for notation comparison and documentation checks only. They do not diagnose vision problems or replace an eye exam.

Visual acuity notation is often rounded to chart lines, so the converted numeric value may be more precise than the original measurement. This page displays converted values with up to 3 decimal places by default.

Common MAR values to LogMAR values conversions
Common reference values for MAR values to logMAR values.
Values are calculated with logMAR = log10(MAR) and rounded for quick lookup.
MAR valuesLogMAR values
0.5 MAR-0.301 logMAR
0.8 MAR-0.097 logMAR
1 MAR0 logMAR
2 MAR0.301 logMAR
4 MAR0.602 logMAR
10 MAR1 logMAR
Examples
Sample inputs using the same formula as the converter.
Example 1
0.5 MAR-0.301 logMAR

Useful for comparing eye chart notation systems. Use the same formula with your exact input if the measurement needs to be documented.

Example 2
2 MAR0.301 logMAR

Useful for translating research tables and clinical references. Use the same formula with your exact input if the measurement needs to be documented.

Example 3
10 MAR1 logMAR

Useful for checking educational vision examples. Use the same formula with your exact input if the measurement needs to be documented.

FAQs
These answers use the same formula as the converter above.
How do I convert MAR values to logMAR values?

Enter the value in MAR values and apply logMAR = log10(MAR). Round the logMAR values result after the conversion, not before.

What is 1 MAR value in logMAR values?

1 MAR equals 0 logMAR with the current rounding setting. Keep more decimal places when the result feeds another calculation.

What is 0.5 MAR in logMAR?

0.5 MAR is -0.301 logMAR. It appears in the lookup table so you can compare it with nearby amounts.

Can I convert logMAR values back to MAR values?

Yes. Use the reverse LogMAR values to MAR values converter if you need to go the other direction.

How accurate is this MAR values to logMAR values conversion?

The calculator runs the formula in your browser and rounds results to 3 decimal places by default. Visual acuity notation is often rounded to chart lines, so the converted numeric value may be more precise than the original measurement.