Inflation: how it works
Rates checked 15 Oct 2026 against ABS Consumer Price Index.
Prices are tracked by the Consumer Price Index (CPI), published every quarter by the Australian Bureau of Statistics. This calculator uses the All groups CPI for the weighted average of the eight capital cities, from the September quarter 1948 to the June quarter 2026. To convert an amount, it multiplies by the ratio of the two quarters' index numbers: value × CPI (later) ÷ CPI (earlier).
The ABS re-based the index in 2025, so the June quarter 2026 is 102.31 and the September quarter 1999 is 47.72. Only the ratio matters, so $100 in September 1999 is worth $100 × 102.31 ÷ 47.72 = $214.40 in June 2026. The average yearly rate is the steady yearly increase that would give the same total change.
The September quarter 2026 figure is due from the ABS in late October 2026. CPI measures average household prices, so your own costs may have risen faster or slower.
General information only, not financial, tax or credit advice. Check your situation with the ATO, your state revenue office or a licensed adviser.
Inflation FAQs
What is $100 from 2000 worth today?
$100 in the June quarter 2000 is worth $209.78 in the June quarter 2026. Prices rose 109.8% in total, an average of 2.89% a year.
What was inflation in the year to June 2026?
3.9%, from a CPI of 98.43 in the June quarter 2025 to 102.31 in the June quarter 2026.
How much have prices risen since 1948?
$100 in the September quarter 1948 is worth $3,950.19 in the June quarter 2026: a rise of 3,850.2%, or an average of 4.84% a year.
When was inflation highest?
Over a year to a June quarter, the highest was 20.7% in the year to June 1952. Inflation was also high through the 1970s and early 1980s: $100 in June 1980 is worth $563.07 in June 2026.
Why is the index around 100 now?
The ABS re-based the CPI to 2025. Re-basing changes every index number by the same proportion, so the ratios this calculator uses, and its results, don't change.