Direct answer
Forex rates in India are set on a daily basis through a mix of market pricing and official reference-rate rules. In day-to-day reality, traders and institutions continuously exchange currencies, and that ongoing buying and selling creates the prevailing exchange rates seen in the market. Separately, official bodies can publish reference rates each business day by applying an established methodology to available market quotes.
How it works (mechanics)
A “forex rate” can mean different things. The spot exchange rate reflects the price for near-term currency exchange driven by supply and demand. Forward rates (used for later exchange) follow from spot expectations plus interest-rate differentials and currency-market pricing conventions.
On top of market pricing, reference rates are often produced with a process that uses observable quotes at a specific cut-off time. That means the reference you see for a given day is not the same as “whatever the market is at this exact second”; it is the result of applying rules to selected inputs within a defined window.
In India, daily reference rates typically depend on: (1) liquidity and the availability of price quotes from participants, (2) the specific time window and method for aggregating those quotes, and (3) any quality checks that filter inconsistent inputs. Because these factors vary by day, the published reference can change even if there is no major policy announcement.
Example checks and what to look for
A practical way to understand daily setting is to compare three elements for the same date:
- The published reference-rate time series for USD/INR (or another pair) across days, to see day-to-day movement.
- The general direction and volatility implied by market activity, since thinner liquidity can widen spreads and increase quote sensitivity.
- Whether you are comparing spot versus forward versus reference rates, since they are calculated with different assumptions and can diverge.
If the reference rate changes sharply on a particular date, the most common independent explanations are shifts in market quotes around the cut-off time, changes in liquidity, or new information affecting expectations.
Limitations and risks
This explanation describes general mechanisms, not a single, fixed “daily formula.” Exact reference-rate methodology can differ by rate type and the specific authority’s published process. Without the precise methodology document for the reference rate you are using, you cannot determine which quotes were included, what cut-off rules applied, or how outliers were handled.
Also, “forex rate” is not one number in all contexts. Comparing a bank quote, a spot market rate, and an official reference rate can produce differences that are normal rather than contradictory. Finally, past daily behavior does not guarantee future rate behavior, because supply-demand conditions and liquidity can change quickly.