Unfortunately, I cannot cover every variable for wire size in the NEC. This table should be a sufficient guide for any individual conductors you may have to install in a conduit while doing residential wiring. It's based off of table 310.15(B). Cable assemblies such as NMB and SE/SER have different properties, please use the appropriate table for them.

Conductor Amperages
Size AWG Copper Amps Aluminum Amps
14
15
--
12
20
15
10
30
25
8
50
40
6
65
50
4
85
65
3
100
75
2
115
90
1
130
100
1/0
150
120
2/0
175
135
3/0
200
155
4/0
230
180
Size kcmil
Copper Amps Aluminum Amps
250
255
205
300
285
230
350
310
250
400
335
270
500
380
310
600
420
340



NMB (Romex) Amperages
Size
Amps
14-2, 14-3
15
12-2, 12-3
20
10-2, 10-3
30
8-2, 8-3
40
6-2, 6-3
55



SE/SER Cable (when used as feeder, not for service)
Size
Amps
4
65
3
75
2
90
1
100
1/0
120
2/0
135
3/0
155
4/0
180
250
205


Conductors and Cables when used as service entrance conductor or to feed the Main sub-panel in a meter-main/sub-panel type service (only use these numbers if your cable is carrying the entire load of your house)
Size
Copper
Aluminum
4
100
--
3
110
--
2
125
100
1
150
110
1/0
175
125
2/0
200
150
3/0
225
175
4/0
250
200
250 kcmil
300
225
350 kcmil
350
300
400 kcmil
400
--
500 kcmil
--
350
600 kcmil
--
400