https://www.dbs.com.sg/iwov-resources/pdf/deposits/multiplier-programme/faq-dbs-multiplier.pdf
Pg 4.
Q2) How is the interest calculated?
The interest is calculated daily.
1. The preferential interest rate is applied to the end-day SGD balance in your DBS Multiplier Account.
2. Interest earned for each balance tier is calculated and rounded off to the nearest 4 decimal places.
3. Each day’s interest earned is summed up and rounded off to the nearest 2 decimal places.
4. The entire month’s interest is then summed up.