How much Income Tax will be deducted on transferring money to India from UK?

Depends entirely on how much.

money wired from anywhere into an Indian citizen's account will count as taxable income regardless if you paid tax already in the UK. there are 4 tax brackets in india (basic personal income)

In rupees

Up to ₹200,000 is 0%

₹200,001–500,000 is 10%

₹500,001–1,000,000 is 20%

Above ₹1,000,000 is 30%

This also does not account for any non tax fees, such as a wire fee, processing fee by the banks, commission, and foreign exchange fee.

My Advice as an international traveler:

If you are sending in anything less than 300000 rupees at a time, carry it in cash the next time you visit india. amounts less than $5000 USD do not have to be declared, it is Duty Free. and carry it in pounds, do not exchange into rupees before you go to india, it is illegal to import rupees into india

If you are transferring your UK earnings on which the taxes were paid at UK, then there will not be any taxes in India for the amount sent by you from UK. You can send as much as you can. There will not be any taxes on that amount. So do not worry.

If no taxes are paid on your salary at UK, then you have to pay taxes at India as per slab rates. The tax slabs given by Gene in his answer are old slabs. So ignore them. The new tax slabs for Male/female less than 60 years are 0-2.5Lakhs=NIL, 2.5L to 5L @10%, 5L to 10L @20% and 10L or more @30%.