How many GJ is 15 t TNT?
15 t TNT = 62.76 GJ
It is 62.76 GJ, so saying 63 GJ is fine — rounding is within 0.5%.
And how many t TNT is 15 GJ?
15 GJ = 3.585 t TNT
Formula: GJ = t TNT × 4.184
t TNT to GJ around this value
6 t TNT25.104GJ
7 t TNT29.288GJ
8 t TNT33.472GJ
9 t TNT37.656GJ
10 t TNT41.84GJ
11 t TNT46.024GJ
12 t TNT50.208GJ
13 t TNT54.392GJ
14 t TNT58.576GJ
15 t TNT62.76GJ
16 t TNT66.944GJ
17 t TNT71.128GJ
18 t TNT75.312GJ
19 t TNT79.496GJ
20 t TNT83.68GJ
21 t TNT87.864GJ
22 t TNT92.048GJ
23 t TNT96.232GJ
24 t TNT100.416GJ
25 t TNT104.6GJ