Data as of Sep 12, 2026. Both funds on the fields they both publish, from the same sources.
MDY vs MGK: how they differ
MDY and MGK hold 0% of their weight in the same names, and MGK returned more over the year.
SPDR S&P MidCap 400 ETF Trust and Vanguard Mega Cap Growth Index Fund.
What they hold in common
By the books each fund has filed, MDY and MGK hold 0% of their money in the same securities at the same weight.
| Only in MDY | Only in MGK |
|---|---|
| TWILIO INC 0.86% | NVIDIA Corp 13.29% |
| CARPENTER TECHNOLOGY CORP 0.85% | Apple Inc 12.19% |
| MKS INC 0.83% | Microsoft Corp 7.52% |
| CURTISS-WRIGHT CORP 0.77% | Alphabet Inc 5.93% |
| ENTEGRIS INC 0.76% | Alphabet Inc 4.67% |
| NVENT ELECTRIC PLC 0.76% | Amazon.com Inc 4.47% |
| ATI INC 0.74% | Broadcom Inc 4.28% |
| ILLUMINA INC 0.73% | Meta Platforms Inc 4.08% |
Weight overlap is an ETFIQ calculation: for every security both funds hold, the smaller of the two weights, summed. Above 50%, holding both is close to holding one of them twice. Holdings dated Jun 30, 2026.
| MDY SPDR S&P MidCap 400 ETF Trust | MGK Vanguard Mega Cap Growth Index Fund | |
|---|---|---|
| Where it sits | Core index fund | Core index fund |
| Issuer | State Street | Vanguard |
| What it is | S&P MidCap 400, book from IJH | Mega Cap Growth |
| Total return, 1 year | +13.0% | +14.9% |
| S&P 500 over the same days | +17.5% | +17.5% |
| Gap to the S&P 500 | −4.5 pts | −2.6 pts |
| Expense ratio | 0.23% | 0.07% |
| Already in the S&P 500 | 0.0% | 99.2% |
| Holdings | 400 | 56 |
MDY in plain words
MDY is an index equity fund tracking the S&P MidCap 400. Over the year to Sep 11, 2026 it returned +13.0% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.23% a year. By its holdings filed for Jun 30, 2026, 0% of the fund by weight is stocks the S&P 500 also holds, across 400 positions, with the top ten at 7.7%. It sat 5.3% below its high of Aug 14, 2026 on Sep 11, 2026.
MGK in plain words
MGK is an index equity fund tracking the Mega Cap Growth. Over the year to Sep 11, 2026 it returned +14.9% with distributions reinvested, against +17.5% for the S&P 500 and +23.0% for the Nasdaq-100. The prospectus expense ratio is 0.07% a year. By its holdings filed for Jun 30, 2026, 99% of the fund by weight is stocks the S&P 500 also holds, across 56 positions, with the top ten at 63.8%.
Questions people ask
- Which returned more over the last year, MDY or MGK?
- In the year to Sep 12, 2026, with distributions reinvested, MDY returned +13.0% and MGK returned +14.9%, so MGK returned more. One year is one year; the longer windows are in the table.
- Which is cheaper, MDY or MGK?
- MDY charges 0.23% a year and MGK charges 0.07%, so MGK is cheaper. Fees come from each fund's prospectus.
- How much do MDY and MGK overlap with the S&P 500?
- By their latest filed holdings, 0% of MDY and 99% of MGK by weight is stocks the S&P 500 already holds. Between the two funds, 0% of their books are the same securities at the same weight.
Other comparisons
Where to next
Where these figures came from
ETFIQ links to the documents behind every figure. It is not affiliated with any issuer, and a link is not an endorsement.
Cite this page. ETFIQ, MDY against MGK, data as of Sep 12, 2026. https://etfiq.com/compare/any/MDY-MGK Free to use with attribution; the underlying files are at Open data.
A comparison is not a recommendation. Standards and sources