Exchange rates are reference points, not offers. This guide explains the forces behind the numbers you see.
Inflation and purchasing power
At its simplest, inflation erodes the purchasing power of a currency. If prices inside a country rise faster than prices elsewhere, each unit of that currency buys less over time — both at home and, eventually, abroad. Persistent high inflation tends to weaken a currency against lower-inflation peers.
This is why economists watch relative inflation rather than inflation in isolation. A currency can hold up reasonably well even with moderate inflation, provided its trading partners are experiencing similar price pressures.
The South Asian context
Currencies such as the Pakistani rupee, Indian rupee, Bangladeshi taka, and Sri Lankan rupee are shaped by a combination of domestic inflation, import dependence, and external financing needs. Many South Asian economies import a large share of their energy and industrial inputs, which links their currencies tightly to global commodity prices.
When global energy prices rise, import bills expand, demand for foreign currency increases, and the local currency can come under pressure. Combine that with elevated domestic inflation and the effect on the exchange rate is amplified.
Central-bank responses
Central banks respond to inflation primarily through interest-rate policy. Raising rates can attract capital and support the currency, but it also slows growth. This trade-off is at the heart of most currency-market narratives you will read.
Because markets are forward-looking, exchange rates often move on the expectation of policy changes rather than the changes themselves. A rate decision that is fully anticipated may cause little movement, while a surprise can trigger a sharp repricing.
What this means for you
If you send or receive money across borders, inflation trends give you context for why rates drift over months and years. They will not help you time a transfer to the day, but they explain the direction of travel and help you set realistic expectations.