If the situation in the question is to entrust an individual to proofread and pay him, then according to the tax law, your unit should withhold and pay personal income tax according to the "income from labor remuneration".

The formula for calculating the taxable amount of personal income tax paid by "income from remuneration for services" is:

1。 Each income of less than 4000 yuan:

Taxable amount = (amount of income per time -800)*20%

2。 Each income is between 4000 yuan and 25000 yuan:

Taxable amount = every income *( 1-20%)*20%

3。 Each income is between 25,000 yuan and 62 500 yuan:

Taxable amount = every income *( 1-20%)*30%-2 000.

4。 Every time the income is above 62 500 yuan:

Taxable amount = every income *( 1-20%)*40%-7 000.

According to your situation, "every time" in the above formula can be calculated as "every month".