Convert Roentgens to Kiloroentgens

Convert Roentgens (R) to Kiloroentgens (kR) instantly and accurately.

Roentgens (R)
Kiloroentgens (kR)

Conversion Formula

kR = R × 0.001

About Roentgens

The roentgen (R) equals exactly 2.58 × 10⁻⁴ C/kg, the historical unit of X-ray and gamma-ray exposure defined in 1928 (ICRU) and redefined exactly in 1962. Still widely used in the US: field survey instruments read in R/h; NRC and EPA regulations cite R and mR; the Chernobyl accounts famously reported readings in R/h. 1 R = 2.58 × 10⁻⁴ C/kg.

About Kiloroentgens

The kiloroentgen (kR) equals 0.258 C/kg. Used in radiation hardness testing of electronics and legacy nuclear weapons effects literature; total ionising exposure inside nuclear facilities during design-basis accident scenarios is cited in kR; some older radiation therapy machine output specifications use kR/min. 1 kR = 0.258 C/kg = 10³ R.

Quick Reference Table

Roentgens (R)Kiloroentgens (kR)
1 R0.001 kR
2 R0.002 kR
5 R0.005 kR
10 R0.01 kR
25 R0.025 kR
50 R0.05 kR
100 R0.1 kR

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