Sri Lanka Inflation Calculator (CCPI) — Rupee Purchasing Power

Sri Lanka's headline inflation measure is the Colombo Consumer Price Index (CCPI), published monthly by the Department of Census and Statistics on a base of December 2013 = 100. The index tracks the price of a fixed basket of goods and services for Colombo-district households; the monthly press release is the official figure quoted in parliament, CBSL Monetary Policy Reviews and the national accounts.

The calculator above ships a verified monthly CCPI series from 2015-01 through 2026-04 and applies four standard CPI formulas to it:

1. Equivalent value across time. The standard rebasing identity: equivalent = amount × CCPI_to / CCPI_from. This is the same formula CBSL uses in the Statistical Appendix to its Annual Report when restating historical figures in constant rupees.
2. Cumulative inflation between the two months: ((CCPI_to − CCPI_from) / CCPI_from) × 100. Reported as a percentage change.
3. Annualised inflation (geometric mean across the months elapsed): ((CCPI_to / CCPI_from) ^ (12 / months) − 1) × 100. This is the single yearly rate that, if compounded over the period, reproduces the cumulative change.
4. Real interest / real salary growth using the exact Fisher form, not the linear approximation: real = ((1 + nominal/100) / (1 + inflation/100) − 1) × 100. Common rule-of-thumb subtraction (nominal − inflation) under-reports the gap at higher rates. The same Fisher adjustment is what tells you whether a deposit beats inflation — pair this with the Sri Lanka fixed deposit calculator to turn a quoted FD rate into a real, inflation-adjusted return.

For the future-projection mode the tool applies straightforward compound growth at the user-supplied annual rate — explicitly labelled as a projection rather than an official CBSL forecast. Every result is cross-checked at module load against the chained month-on-month product of the same CCPI series, so a corrupted data file is detected before the page renders.

A word on what the index actually measures. CCPI is a fixed-basket Laspeyres-type index: the Department of Census and Statistics prices the same representative basket of goods and services each month and weights each category — food and non-alcoholic beverages, housing, transport, health, education and the rest — by its share of average household spending in the base period. Because the weights are fixed, the index captures pure price change rather than shifts in what people buy. That is precisely why it is the right tool for restating a past rupee figure: it isolates how much more money you would need today to buy the identical basket, holding the basket constant.

Two edge cases are worth understanding before you read a result. First, the index is not monotonic. Sri Lanka saw outright deflation across parts of 2024, so a From-month chosen in early 2023 can return a negative cumulative figure against a 2024 end-month — the calculator labels this as deflation rather than treating it as an error. Second, annualised inflation is a geometric mean, not the simple cumulative figure divided by years: comparing September 2022 (the crisis peak) to today gives a low annualised rate because most of the price jump happened before the peak, so very little additional inflation accrued afterward. The worked examples below reproduce both cases with full arithmetic.

Inflation rarely matters in isolation. The same CCPI movement that erodes a salary also shapes loan affordability and tax brackets, so it is worth reading this result alongside your monthly repayment on the Sri Lanka loan EMI calculator and your take-home pay on the Sri Lanka income tax calculator. A nominal raise that looks generous can shrink in real terms once inflation and a higher tax band are both applied.

The series is reviewed every month against the latest DCS press release; the last-verified date is exported as LAST_VERIFIED in the data module (2026-05-16) and shown in the calculator card's footer strip.

• Department of Census and Statistics — Monthly CCPI series (base 2013 = 100)
• Department of Census and Statistics — CCPI monthly press releases (PDF)
• Central Bank of Sri Lanka — Inflation Statistics dashboard (secondary cross-check)
• Central Bank of Sri Lanka — Monetary Policy Reviews (forward inflation target)

The CCPI series in this calculator was last cross-checked against the DCS sources above on 2026-05-16, with coverage from 2015-01 to 2026-04. The page refreshes on the orchestrator's monthly cadence after each new DCS bulletin.