Blue Yellow Violet Gold — 640 MΩ
Read left to right, starting from the end where the bands are grouped. The gold band is the tolerance and always sits alone at the far end.
Value
640 MΩ
Range at ±5%
608 MΩ – 672 MΩ
Standard value
Non-standard
No E24 part carries this value — check you are reading from the right end.
What each band says
| Band | Colour | Meaning |
|---|---|---|
| 1 | Blue | 1st digit — 6 |
| 2 | Yellow | 2nd digit — 4 |
| 3 | Violet | Multiplier — ×10M |
| 4 | Gold | Tolerance — ±5% |
In a circuit
Across 5 V
0.00781 µA · 0.0391 µW · 1/8 W part
Across 12 V
0.0187 µA · 0.225 µW · 1/8 W part
Surface-mount marking for the same value: 647.
If you misread one band
Brown and red, or orange and red, are easy to confuse under a desk lamp. These are the codes one band away from this one.