Decimal acuity values to LogMAR values Converter
Convert decimal acuity values to logMAR values using logMAR = -log10(decimal acuity). The formula is logMAR = -log10(decimal acuity); 1 decimal is 0 logMAR.
A visual acuity notation equal to the Snellen numerator divided by the denominator.
The base-10 logarithm of MAR, often used in vision research and chart scoring.
Start with your value in decimal acuity values, then apply the formula below. It stays visible so you can catch rounding mistakes instead of just copying the output.
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.
| Decimal acuity values | LogMAR values |
|---|---|
| 0.1 decimal | 1 logMAR |
| 0.2 decimal | 0.699 logMAR |
| 0.5 decimal | 0.301 logMAR |
| 1 decimal | 0 logMAR |
| 1.25 decimal | -0.097 logMAR |
| 2 decimal | -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.
Useful for translating research tables and clinical references. Use the same formula with your exact input if the measurement needs to be documented.
Useful for checking educational vision examples. Use the same formula with your exact input if the measurement needs to be documented.
How do I convert decimal acuity values to logMAR values?
Enter the value in decimal acuity values and apply logMAR = -log10(decimal acuity). Round the logMAR values result after the conversion, not before.
What is 1 decimal acuity value in logMAR values?
1 decimal equals 0 logMAR with the current rounding setting. Keep more decimal places when the result feeds another calculation.
What is 0.1 decimal in logMAR?
0.1 decimal is 1 logMAR. It appears in the lookup table so you can compare it with nearby amounts.
Can I convert logMAR values back to decimal acuity values?
Yes. Use the reverse LogMAR values to Decimal acuity values converter if you need to go the other direction.
How accurate is this decimal acuity 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.