Shipping rates are often calculated based on the parcel weight, size, and sometimes distance. Here are the local postage rates by Singapore Post, as of August 2021, for your reference.
1 Postcards or mail items in card form will be considered as Standard Mail if dimensions do not exceed 240mm x 162mm with paper quality of at least 230gsm.
2 Printed papers include but are not limited to paper based items like annual reports, books, catalogues, direct mail, newspapers or periodicals.
3 Mail and packages sent via Tracked services must not exceed the maximum dimensions of 324mm x 229mm x 65mm and maximum weights of 500g for mail and 2kg for packages. Additional surcharge may apply for oversized and/or overweight items.
Note: These are just estimated shipping prices that you will need to pay to Singpost. Please double-check with your courier provider for a more accurate rate.