How much does $100,000 earn at 4.5% APY with daily compounding for 10 years?

$100,000 at 4.5% APY compounded daily for 10 years grows to $156,827 — interest earned $56,827. The effective APY after daily compounding is 4.602%, slightly higher than the 4.5% nominal rate because each day's interest earns interest the next day.

A = P × (1 + r/365)^(365 × t) where P = $100,000 principal, r = 0.0450 annual rate as decimal, 365 = compounding periods per year, t = 10 years. Plugging in: $100,000 × (1 + 0.000123)^3650 = $156,827.

Is 4.5% APY realistic in 2026?

Yes — 4.5% is conservative for 2026 HYSA and CD rates, well within the realistic range for major online banks (Marcus, Ally, Discover, SoFi).

Does daily compounding actually matter vs monthly?

Slightly. The gap between daily and monthly compounding at the same nominal rate is small: at 5% APR over 1 year, daily produces APY 5.127% vs monthly 5.116% — about $1 per $10,000 difference. Over 30 years on the same balance, the gap widens to roughly $150 because the rate gap compounds. Compounding frequency is much less important than the headline rate (APY) and your time horizon.

Daily compound scenario · Verified 2026-06-15

$100,000 at 4.5% APY daily compound for 10 years

Grows to $156,827. You earn $56,827 in interest at an effective APY of 4.602%.

Final balance

$156,827

Interest earned

$56,827

Effective APY

4.602%

Quick context

Long-term wealth preservation.

How this number was calculated

Daily compound interest formula with n = 365 compounding periods per year:

A = P × (1 + r/n)^(n × t)

where:
  P = $100,000          (principal)
  r = 0.0450              (annual rate as decimal)
  n = 365                  (compounding periods per year — daily)
  t = 10                   (years)

Daily rate = r/n = 0.000123     (0.01230% per day)

Final balance = $100,000 × (1 + 0.000123)^3650
              = $156,827

Interest earned = $156,827 − $100,000 = $56,827
Effective APY = (1 + 0.000123)^365 − 1 = 4.602%

Same closed-form math used by Investor.gov (SEC) and the Federal Reserve. Want to run a different combination? Open the full calculator.

Year-by-year breakdown

Year	Interest earned	Year-end balance
1	$4,603	$104,603
2	$4,814	$109,417
3	$5,036	$114,453
4	$5,268	$119,720
5	$5,510	$125,231
6	$5,764	$130,994
7	$6,029	$137,023
8	$6,306	$143,330
9	$6,597	$149,927
10	$6,900	$156,827

Related daily-compound scenarios

$1,000 at 5% APY daily compound for 1 year

→ $1,051 (1 year at 5%)

$1,000 at 5% APY daily compound for 10 years

→ $1,649 (10 years at 5%)

$5,000 at 5% APY daily compound for 5 years

→ $6,420 (5 years at 5%)

$10,000 at 5% APY daily compound for 1 year

→ $10,513 (1 year at 5%)

Try different inputs

Full daily compound interest calculator

Change principal, APY, or years to model your exact HYSA, CD, or money market scenario. Visual chart and year-by-year breakdown included.

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Educational tool. APY rates fluctuate with Federal Reserve policy and the rate environment; verify the current rate at your bank's product page before relying on this projection. Past rates do not guarantee future rates. Verified 2026-06-15.