The Real gross domestic product (GDP) growth year-on-year percentage forecast tells us how much a country’s production of goods and services is expected to increase over a 12-month period, with inflation removed. 

This helps us spot the fastest-growing economy. 

It reveals which countries are actually producing and earning more in real terms, rather than just appearing to grow because prices have risen.

Using the latest available data from the OECD Economic Outlook, the visualization above shows year-on-year real GDP growth figures for all G20 economies. 

It includes 2025 actuals and 2026-2027 projections.

TL;DR

• India leads all G20 economies with 7.6% real GDP growth in 2025, projected to remain the fastest-growing major economy at 6.3% in 2026 and 6.4% in 2027.
• Germany recorded the lowest GDP growth among G20 economies, while France, Italy, and Japan reflect a broader story of stagnation in Europe and among developed economies.

The OECD projects India at 6.3% in 2026 and 6.4% in 2027, making India the only major economy in the top five whose 2027 projection exceeds its 2026 figure. 

The OECD attributes the 2026 moderation in part to trade policy uncertainty stemming from US tariff changes affecting Asian export-linked economies. 

ALSO READ: Data Shows World Will Spend $7.6 Trillion on AI by 2031

Issues from the European and Japanese

Germany, at 0.3%, is the floor of a consistently low growth in the healthy European picture. 

Italy, France, and the UK posted 0.5%, 0.9%, and 1.4%, respectively. 

Germany’s recovery trajectory in the OECD projection (0.3% in 2025, 0.7% in 2026, 1.1% in 2027) represents an accelerating recovery from a very low base. 

The specific structural pressures behind the 0.3% figure include energy cost disruptions from the loss of Russian gas supply, the automotive sector’s exposure to Chinese electric-vehicle competition, and weak domestic demand. 

The OECD projects Germany to recover, but to growth rates that remain below the world average through 2027.

U.S. Below the World Average

The world’s largest economy grew by 2.1% in 2025, below the OECD’s World average of 3.4% and the G20 aggregate of 3.3%. 

To put it another way, that is 2.0% against a world average of 2.8% in 2026 and 1.8% against 3.1% in 2027.

The US is projected to grow below the world average in all three years of the forecast, with the deceleration consistent and directionally unambiguous.

The 2026 world growth deceleration corresponds to the OECD’s central estimate of the near-term cost of the Trump administration’s April 2025 tariff announcements to global economic output. 

ALSO READ: Gold Reserves: Nations With The Most “Untouchable” Wealth

ELI5 (Explain It Like I’m 5)

According to the OECD’s June 2026 report, India’s economy is growing faster than any other large economy, at 7.6% in 2025, and will remain the fastest through 2027. 

Germany grew the slowest at just 0.3% (about 25 times slower than India). 

The US is growing, too, but more slowly than the global average.

South Korea is expected to nearly triple its growth rate in 2026, driven by the global boom in AI chips. Most rich Western countries are growing slowly, while Asian economies are growing fast.

Source: 

OECD Economic Outlook, June 2026.