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Exhibit 23.1
CONSENT OF INDEPENDENT AUDITORS
We consent to the reference to our firm under the caption "Experts" in the
Registration Statement (Form S-4) and related Prospectus of Media Metrix, Inc.
for the registration of 19,046,596 shares of its common stock and to the
incorporation by reference therein of our report dated January 28, 2000, except
for the last three paragraphs of Note 15, as to which the date is March 8, 2000,
with respect to the consolidated financial statements and schedule included in
its Annual Report (Form 10-K) for the year ended December 31, 1999, filed with
the Securities and Exchange Commission.
/s/Ernst & Young LLP
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Ernst & Young LLP
New York, New York
July 26, 2000
