Convert Milliroentgen to Gray

Enter the number of milliroentgens that you want to convert to grays.

1 mR (milliroentgens) = 8.77e-6 Gy (grays)

How to Convert Milliroentgens to Grays

The milliroentgen and gray are both units of radiation dose. 1 gray equals 114025.08552 milliroentgens. This means to convert milliroentgens to grays, you divide by 114025.08552.

Formula

grays = milliroentgens ÷ 114025.08552

Step-by-Step Example

Convert 5 mR to grays:

1
Convert 5 mR to grays

We need to convert milliroentgens to grays

2
Apply the formula

Since 1 Gy = 114025.08552 mR, divide by 114025.08552

5 ÷ 114025.08552 = 4.385e-5

Answer

5 mR = 4.385e-5 Gy

Milliroentgen to Gray Conversion Table

Quick reference table for common milliroentgen to gray conversions. Click any value for detailed calculation.

Milliroentgens (mR) Grays (Gy)
0.1 mR 8.77e-7 Gy
0.5 mR 4.385e-6 Gy
1 mR 8.77e-6 Gy
2 mR 1.754e-5 Gy
5 mR 4.385e-5 Gy
10 mR 8.77e-5 Gy
25 mR 0.00021925 Gy
50 mR 0.0004385 Gy
100 mR 0.000877 Gy

About These Units

Milliroentgen (mR)

A milliroentgen (mR) equals 0.001 roentgen. Radiation survey meters often display mR/h for monitoring X-ray and gamma fields. Natural background: 10-20 mR/year. Typical survey meter range: 0-1000 mR/h.

Gray (Gy)

The gray (Gy) is the SI unit of absorbed dose: energy deposited per unit mass (1 Gy = 1 J/kg). Named after Louis Harold Gray. For gamma/X-rays and beta particles, 1 Gy ≈ 1 Sv (quality factor Q=1). Radiation therapy total dose: 40-80 Gy.

Frequently Asked Questions

How do I convert milliroentgens to grays?

To convert milliroentgens to grays, divide the value by 114025.08552. For example, 10 mR = 8.77e-5 Gy.

How many grays are in 1 milliroentgen?

1 milliroentgen equals 8.77e-6 grays.

What is the formula for milliroentgens to grays?

The formula is: Gy = mR ÷ 114025.08552.