FLAPX vs. FLXSX

Last updated Apr 1, 2026

Compare and contrast key facts about Fidelity Flex Mid Cap Index Fund (FLAPX) and Fidelity Flex Small Cap Index Fund (FLXSX).

FLAPX is managed by Fidelity. It was launched on Mar 9, 2017. FLXSX is managed by Fidelity. It was launched on Mar 9, 2017.

Performance

FLAPX vs. FLXSX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity Flex Mid Cap Index Fund (FLAPX) and Fidelity Flex Small Cap Index Fund (FLXSX). The values are adjusted to include any dividend payments, if applicable.

FLAPX vs. FLXSX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
FLAPX Fidelity Flex Mid Cap Index Fund	-0.79%	14.33%	15.30%	17.28%	-17.28%	22.59%	17.30%	30.56%	-9.10%	14.01%
FLXSX Fidelity Flex Small Cap Index Fund	-3.13%	12.02%	11.67%	17.11%	-20.29%	14.84%	20.06%	25.69%	-11.13%	14.28%

Returns By Period

In the year-to-date period, FLAPX achieves a -0.79% return, which is significantly higher than FLXSX's -3.13% return.

FLAPX

• 1D: -1.02%
• 1M: -8.39%
• YTD: -0.79%
• 6M: 1.43%
• 1Y: 17.43%
• 3Y*: 13.78%
• 5Y*: 7.53%
• 10Y*: —

FLXSX

• 1D: -1.59%
• 1M: -8.74%
• YTD: -3.13%
• 6M: -1.03%
• 1Y: 19.83%
• 3Y*: 11.35%
• 5Y*: 2.86%
• 10Y*: —

*Multi-year figures are annualized to reflect compound growth (CAGR)

FLAPX vs. FLXSX - Expense Ratio Comparison

FLAPX has a 0.00% expense ratio, which is lower than FLXSX's 0.00% expense ratio. Despite the difference, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

FLAPX

Fidelity Flex Mid Cap Index Fund

FLXSX

Fidelity Flex Small Cap Index Fund

Return for Risk

FLAPX vs. FLXSX — Risk / Return Rank

Compare risk-adjusted metric ranks to identify better-performing investments over the past 12 months.

FLAPX

FLAPX Risk / Return Rank: 48
FLAPX Sharpe Ratio Rank: 46
FLAPX Sortino Ratio Rank: 49
FLAPX Omega Ratio Rank: 45
FLAPX Calmar Ratio Rank: 46
FLAPX Martin Ratio Rank: 52

FLXSX

FLXSX Risk / Return Rank: 40
FLXSX Sharpe Ratio Rank: 40
FLXSX Sortino Ratio Rank: 43
FLXSX Omega Ratio Rank: 34
FLXSX Calmar Ratio Rank: 45
FLXSX Martin Ratio Rank: 38

The rank (0–100) shows how this investment's returns compare to the risk taken. Higher = better. Based on the past 12 months of data, combining Sharpe, Sortino, and other metrics used by quantitative funds and institutional investors.

FLAPX vs. FLXSX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Flex Mid Cap Index Fund (FLAPX) and Fidelity Flex Small Cap Index Fund (FLXSX). Risk-adjusted metrics are performance indicators that assess an investment's returns in relation to its risk, enabling a more accurate comparison of different investment options.

	FLAPX	FLXSX	Difference
Sharpe ratio Return per unit of total volatility	0.90	0.82	+0.08
Sortino ratio Return per unit of downside risk	1.37	1.28	+0.09
Omega ratio Gain probability vs. loss probability	1.19	1.16	+0.03
Calmar ratio Return relative to maximum drawdown	1.13	1.11	+0.02
Martin ratio Return relative to average drawdown	5.07	4.00	+1.07
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

FLAPX vs. FLXSX - Sharpe Ratio Comparison

The current FLAPX Sharpe Ratio is 0.90, which is comparable to the FLXSX Sharpe Ratio of 0.82. The chart below compares the historical Sharpe Ratios of FLAPX and FLXSX, offering insights into how both investments have performed under varying market conditions. These values are calculated using daily returns over the previous 12 months.

Sharpe Ratios by Period

	FLAPX	FLXSX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.90	0.82	+0.08
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.41	0.13	+0.28
Sharpe Ratio (All Time) Calculated using the full available price history	0.53	0.33	+0.20

Correlation

The correlation between FLAPX and FLXSX is 0.93, which is considered to be high. That indicates a strong positive relationship between their price movements. Having highly-correlated positions in a portfolio may signal a lack of diversification, potentially leading to increased risk during market downturns.

Dividends

FLAPX vs. FLXSX - Dividend Comparison

Neither FLAPX nor FLXSX has paid dividends to shareholders.

	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017
FLAPX Fidelity Flex Mid Cap Index Fund	0.00%	0.00%	1.08%	1.99%	1.82%	2.83%	2.16%	2.18%	2.24%	0.44%
FLXSX Fidelity Flex Small Cap Index Fund	0.00%	0.00%	1.36%	1.49%	1.26%	2.74%	1.06%	2.86%	2.31%	0.77%

Drawdowns

FLAPX vs. FLXSX - Drawdown Comparison

The maximum FLAPX drawdown since its inception was -40.31%, roughly equal to the maximum FLXSX drawdown of -41.72%. Use the drawdown chart below to compare losses from any high point for FLAPX and FLXSX.

Drawdown Indicators

	FLAPX	FLXSX	Difference
Max Drawdown Largest peak-to-trough decline	-40.31%	-41.72%	+1.41%
Max Drawdown (1Y) Largest decline over 1 year	-13.40%	-13.94%	+0.54%
Max Drawdown (5Y) Largest decline over 5 years	-26.09%	-31.88%	+5.79%
Current Drawdown Current decline from peak	-9.21%	-12.25%	+3.04%
Average Drawdown Average peak-to-trough decline	-6.21%	-10.60%	+4.39%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.00%	4.10%	-1.10%

Volatility

FLAPX vs. FLXSX - Volatility Comparison

The current volatility for Fidelity Flex Mid Cap Index Fund (FLAPX) is 6.04%, while Fidelity Flex Small Cap Index Fund (FLXSX) has a volatility of 7.04%. This indicates that FLAPX experiences smaller price fluctuations and is considered to be less risky than FLXSX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	FLAPX	FLXSX	Difference
Volatility (1M) Calculated over the trailing 1-month period	6.04%	7.04%	-1.00%
Volatility (6M) Calculated over the trailing 6-month period	11.93%	14.95%	-3.02%
Volatility (1Y) Calculated over the trailing 1-year period	20.19%	23.66%	-3.47%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	18.49%	22.65%	-4.16%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	20.02%	24.08%	-4.06%