US vs International Stocks: Which Grows $10,000 More?

How US vs international stocks are compared

On the defaults — a $10,000.00 lump sum in each market for 20 years, US stocks at 10% and international stocks at 6% — the US ending is $73,280.74 and the international ending is $33,102.04, so US stocks win by $40,178.70. The whole comparison is three moves: grow the lump sum in the US market, grow the same lump sum in the international market, and subtract the two endings.

Five things about the model are worth stating plainly. First, each ending is the lump sum times (1 + return ÷ 12)^(12 × years) — $10,000.00 × (1 + 10% ÷ 12)^240 = $73,280.74 for the US side and $10,000.00 × (1 + 6% ÷ 12)^240 = $33,102.04 for the international side. Second, the growth is the ending minus the lump sum — $73,280.74 − $10,000.00 = $63,280.74 for the US side and $33,102.04 − $10,000.00 = $23,102.04 for the international side. Third, the winner is the higher ending and the gap is the difference of the two displayed endings — $73,280.74 − $33,102.04 = $40,178.70 — and a rounded gap of $0.00 is a tie. Fourth, the default returns — US 10%, international 6% — are illustrative long-run assumptions, not forecasts: actual returns vary year to year, and international stocks beat US stocks in some decades. And fifth, the model treats each market as one flat return and ignores taxes, fund fees, currency moves, and the timing of dividends; all listed in Accuracy & limitations.

The worked example, line by line

Setup: $10,000.00 lump sum, US return 10%, international return 6%, 20 years.

Line 1 — grow the lump sum in the US market. The US ending is $10,000.00 × (1 + 10% ÷ 12)^240 = $73,280.74, a growth of $63,280.74.

Line 2 — grow the same lump sum in the international market. The international ending is $10,000.00 × (1 + 6% ÷ 12)^240 = $33,102.04, a growth of $23,102.04.

Line 3 — subtract the endings. The gap is $73,280.74 − $33,102.04 = $40,178.70, and the winner is US stocks.

Every branch, checked

international 8%: Lump $10,000.00, US 10.00%, international 8.00%, 20 years: US ending $73,280.74 (growth $63,280.74), international ending $49,268.03 (growth $39,268.03), US stocks win by $24,012.71 — An 8% international return instead of 6% shrinks the gap to $24,012.71 — the return is the whole story.

US 8%: Lump $10,000.00, US 8.00%, international 6.00%, 20 years: US ending $49,268.03 (growth $39,268.03), international ending $33,102.04 (growth $23,102.04), US stocks win by $16,165.99 — An 8% US return instead of 10% shrinks the gap to $16,165.99.

horizon 30 years: Lump $10,000.00, US 10.00%, international 6.00%, 30 years: US ending $198,373.99 (growth $188,373.99), international ending $60,225.75 (growth $50,225.75), US stocks win by $138,148.24 — Ten more years widen the gap to $138,148.24 — compounding rewards the higher return more the longer it runs.

lump sum $50,000: Lump $50,000.00, US 10.00%, international 6.00%, 20 years: US ending $366,403.68 (growth $316,403.68), international ending $165,510.22 (growth $115,510.22), US stocks win by $200,893.46 — Five times the lump sum, five times the gap: $200,893.46.

international 10%: Lump $10,000.00, US 10.00%, international 10.00%, 20 years: US ending $73,280.74 (growth $63,280.74), international ending $73,280.74 (growth $63,280.74), Tie — The same return on both sides is an exact tie — $73,280.74 each and a $0.00 gap.

horizon 10 years: Lump $10,000.00, US 10.00%, international 6.00%, 10 years: US ending $27,070.41 (growth $17,070.41), international ending $18,193.97 (growth $8,193.97), US stocks win by $8,876.44 — Ten years instead of twenty shrinks the gap to $8,876.44.

US 12%: Lump $10,000.00, US 12.00%, international 6.00%, 20 years: US ending $108,925.54 (growth $98,925.54), international ending $33,102.04 (growth $23,102.04), US stocks win by $75,823.50 — A 12% US return instead of 10% widens the gap to $75,823.50.

The reverses, worked backwards

Lump sum for a $5,000.00 gap: $1,244.44 — the exact lump sum is 1244.4407. At the displayed $1,244.44 the US ending is $9,119.35 and the international ending is $4,119.35, a gap of $5,000.00 (exact to the cent). $1,243.44 gives a gap of $4,995.98; $1,245.44 gives a gap of $5,004.02. The star is DOLLARS.

International return for an exact tie: 10.00% — the tie return equals the US return under the same compounding. At 10.00% both endings are $73,280.74 and the gap is $0.00 (exact tie). At 9.99% the gap is $145.21; at 10.01% the gap is $145.49. The star is a PERCENT.

Horizon for the gap to reach $10,000: 11 years — the smallest whole-year horizon with a gap of $10,000 or more. At 11 years the gap is $10,588.91; at 10 years it is $8,876.44. This is a step reverse: years come in whole years here, so there is no exact in-between. The star is YEARS.

US return for a $50,000.00 US ending: 8.07% — the exact US return is 8.0742%. At the displayed 8.07% the US ending is $49,957.98, $42.02 under the $50,000.00 target — rounding. 8.06% gives $49,858.83; 8.08% gives $50,057.33. The star is a PERCENT.

International return for a $30,000.00 international ending: 5.51% — the exact international return is 5.5057%. At the displayed 5.51% the international ending is $30,025.97, $25.97 over the $30,000.00 target — rounding. 5.50% gives $29,966.26; 5.52% gives $30,085.81. The star is a PERCENT.

Lump sum for a $100,000.00 US ending: $13,646.15 — the exact lump sum is 13646.1511. At the displayed $13,646.15 the US ending is $99,999.99, $0.01 under the $100,000.00 target — rounding. $13,645.15 gives $99,992.66; $13,647.15 gives $100,007.32. The star is DOLLARS.

What the defaults assume

The defaults are a $10,000.00 lump sum, a 10.00% US return, a 6.00% international return, and 20 years — US ending $73,280.74, international ending $33,102.04, gap $40,178.70. With a horizon of 0 years, Lump $10,000.00, US 10.00%, international 6.00%, 0 years: US ending $10,000.00 (growth $0.00), international ending $10,000.00 (growth $0.00), Tie — no time, no growth. With a lump sum of $0, Lump $0.00, US 10.00%, international 6.00%, 20 years: US ending $0.00 (growth $0.00), international ending $0.00 (growth $0.00), Tie. With a US return of 0%, Lump $10,000.00, US 0.00%, international 6.00%, 20 years: US ending $10,000.00 (growth $0.00), international ending $33,102.04 (growth $23,102.04), international stocks win by $23,102.04 — the flip: a flat US market loses to any positive international return. With an international return of 0%, Lump $10,000.00, US 10.00%, international 0.00%, 20 years: US ending $73,280.74 (growth $63,280.74), international ending $10,000.00 (growth $0.00), US stocks win by $63,280.74. With a horizon of 40 years, Lump $10,000.00, US 10.00%, international 6.00%, 40 years: US ending $537,006.63 (growth $527,006.63), international ending $109,574.54 (growth $99,574.54), US stocks win by $427,432.09. With an international return of -2%, Lump $10,000.00, US 10.00%, international -2.00%, 20 years: US ending $73,280.74 (growth $63,280.74), international ending $6,700.96 (growth $-3,299.04), US stocks win by $66,579.78 — a negative return means the international holding shrinks below the starting lump sum.

Output · formula · meaning

Who uses this

• The investor with $10,000.00 choosing a market: they learn the US ending is $73,280.74 and the international ending is $33,102.04 — and they check the 10.00% reverse to see the international return that ties the two markets.
• The investor who expects 8% from international stocks: they learn the gap is $24,012.71 — and they check the $1,244.44 reverse to see the lump sum for a $5,000.00 gap.
• The investor with 30 years: they learn the gap is $138,148.24 — and they check the 11-year reverse to see when the gap first passes $10,000.00.
• The investor with $50,000.00: they learn the gap is $200,893.46 — and they check the 8.07% reverse to see the US return for a $50,000.00 ending.

Accuracy & limitations

The math is first-principles: each ending is the lump sum times (1 + return ÷ 12)^(12 × years), the gap is the difference of the two displayed endings, and the winner is decided from that rounded gap. Every figure is rounded to cents half-up. What the model cannot do is tell you which market will win: it is a comparison of assumptions, not a forecast — it does NOT model returns that change year to year; it does NOT model taxes, fund fees, or currency moves; it does NOT model the timing of dividends; and it treats each market as one flat return, which no real market delivers. The default returns — US 10%, international 6% — are illustrative long-run assumptions, and international stocks beat US stocks in some decades, so past averages do not predict the next 20 years. Use it to see how much the return matters — then check a diversified plan before you act on it.

Frequently asked questions