Gst on web development services

GST applicable as you are providing services outside India which covers under the Export of service so you need to take registration for the same. there are 2 way for taking the same.
1. Normal GST registration- In this you have to pay IGST on the export value in GSTR 3B (zero rated supply)and the same you can claim as refund.
2. Registration + LUT- Under this you need not to pay GST on export value simply you can show the export value under Zero rated supply.