ETF comparison
IJR vs MDY
US Small Cap vs US Mid Cap.
iShares Core S&P Small-Cap ETF · State Street SPDR S&P MIDCAP 400 ETF Trust
Holdings overlap
7 positions appear in both funds. Buying equal dollars of IJR and MDY would leave roughly 2.0% of each dollar exposed to the same underlying securities.
Unmatched is the part of a fund's weight the other fund doesn't match: names only it holds, plus any extra weight it puts in names both funds hold.
Side by side
Sub-score comparison
Tracking quality isn't part of the composite — see what we don't score for why.
Cost difference
IJR is 17 bps cheaper than MDY. On a $100,000 position that's about $170/yr more in fees for MDY.
Fee figure is the annual expense charged on $100,000. To see how the gap compounds over a multi-decade holding period, open the cost calculator pre-filled with IJR vs MDY.
Top shared holdings
7 shared in total| # | Holding | In IJR | In MDY | Overlap |
|---|---|---|---|---|
| 1 | GLAUKOS CORP | 0.44% | 0.41% | 0.41% |
| 2 | BRIGHTSPRING HEALTH SERVICES INC | 0.60% | 0.34% | 0.34% |
| 3 | MOLINA HEALTHCARE INC | 0.64% | 0.34% | 0.34% |
| 4 | BRINKER INTERNATIONAL INC | 0.39% | 0.27% | 0.27% |
| 5 | KRYSTAL BIOTECH INC | 0.53% | 0.24% | 0.24% |
| 6 | CORCEPT THERAPEUTICS INC | 0.45% | 0.22% | 0.22% |
| 7 | FORMFACTOR INC | 0.67% | 0.19% | 0.19% |
Only in IJR
596 total- VIASAT INC 0.66%
- ARGAN INC 0.60%
- ELEMENT SOLUTIONS INC 0.59%
- MAXLINEAR INC 0.58%
- ESCO TECHNOLOGIES INC 0.49%
- MATCH GROUP INC 0.48%
- ALKERMES PLC 0.47%
- EVERUS CONSTRUCTION GROUP INC 0.46%
- STONEX GROUP INC 0.46%
- RALLIANT CORP 0.45%
Only in MDY
394 total- U.S. Dollar 0.77%
- United Therapeutics Corporation 0.75%
- TechnipFMC plc 0.72%
- ATI Inc 0.70%
- US Foods Holding Corp. 0.68%
- Tenet Healthcare Corporation 0.67%
- Reliance Inc. 0.65%
- XPO Inc. 0.63%
- Entegris Inc. 0.63%
- Roku Inc. Class A 0.62%
Related comparisons
More comparisons with IJR
- IJR vs ESGV · Vanguard ESG U.S. Stock ETF 1.9%
- IJR vs AVLV · Avantis US Large Cap Value ETF 1.8%
- IJR vs DVY · iShares Select Dividend ETF 1.7%
- IJR vs FDL · First Trust Morningstar Dividend Leaders Index Fund 1.7%
- IJR vs JQUA · JPMorgan U.S. Quality Factor ETF 1.6%
- IJR vs IWP · iShares Russell Mid-Cap Growth ETF 1.3%
More comparisons with MDY
Percentages are holdings overlap with the named fund.
Open IJR or MDY at a brokerage
Both funds trade commission-free at major US brokerages.
Affiliate links — opening an account through these earns PlainIndex a one-time referral. Scoring is computed before any affiliate consideration; see our methodology and funding disclosure.
Holdings overlap is the sum of min(weight_a, weight_b) over positions
matched on ISIN (CUSIP fallback). Methodology: see
/methodology/.
Comparing two funds doesn't endorse swapping one for the other. Tax-lot history, account type, and personal goals matter — PlainIndex publishes data and methodology, not investment advice.