UK Inflation Calculator

This calculator helps you see how the value of the British Pound (£) changes over time. You can compare equivalent buying power between two dates and understand how inflation affects everyday costs in the United Kingdom.

Understanding CPI and Inflation

The "Weekly Shop" Analogy

Think of a typical weekly shop in the UK: groceries, transport, utility bills, and a few household essentials. If you bought the same basket every month, the total would rise and fall over time.

The Consumer Price Index (CPI) tracks this idea at a national level. It measures how prices change for a representative basket of goods and services. The CPI number reflects the average cost of that basket.

What is Inflation?

Inflation means the general price level rises over time. When inflation is positive, each pound buys a bit less than before.

Inflation Rate (YoY)

The Year-over-Year (YoY) inflation rate compares prices in a given month with the same month one year earlier.

Key Concepts

• Purchasing Power: What your money can actually buy.
• Disinflation: Inflation is still positive, but rising more slowly.
• Deflation: Prices fall overall, which is less common and often short-lived in modern UK data.

Historical Inflation Trends in the United Kingdom

The UK has experienced several distinct inflation periods. In the 1970s and early 1980s, inflation was high and volatile. Later, inflation was comparatively lower and more stable for many years after inflation-targeting frameworks became established.

More recently, the UK saw a sharp jump in inflation following pandemic-era supply disruptions and the energy-price shock in 2021–2023. As global supply chains normalized and energy pressures eased, inflation began to cool, though levels and pace varied month by month.

Original CPI Data Table

Browse the original monthly CPI values used for our calculations below.

FAQ

How do you calculate the adjusted value?

We use a CPI ratio between the base date and the target date.

• $\text{Value}_{base}$: The original pound amount.
• $CPI_{base}$: CPI index at the starting date.
• $CPI_{target}$: CPI index at the ending date.

Why might your result differ from other inflation figures?

Different sources may apply seasonal adjustments, index methods, or annual aggregation rules differently. For clarity and consistency, this tool uses the monthly OECD CPI series directly.

Quick Tips for Interpreting Results

• Adjusted amount is higher: Purchasing power has decreased (inflation).
• Adjusted amount is lower: Purchasing power has increased over the selected period.
• Long periods can look dramatic: Small yearly changes can compound into large differences over decades.

Data Source

The data powering this calculator comes from the Organisation for Economic Co-operation and Development (OECD).

• Provider: OECD
• Dataset: Consumer price indices (CPIs, HICPs), COICOP 1999