The unit of percentage error is
Same as that of physical quantity
Different from that of physical quantity
Percentage error is unit less
Errors have got their own units which are different from that of physical quantity measured
The unit of percentage error is
$\%$ error $=\left(\frac{\text { measused }-\text { exact value }}{\text { exact value }} \times 100\right)$
Her, we are talking about ratio of same unit so from here we cansaly that - error is uniture.