* Facebook jumps after quarterly results beat expectations
* Twitter falls on weaker-than-expected user growth
* P&G, MasterCard, Comcast rise after strong results
* Durable goods order for June rises
* Futures up: Dow 13 pts, S&P 4.25 pts, Nasdaq 42.5 pts (Adds details, comment, updates prices)
July 27 (Reuters) - U.S. stock index futures looked set to open higher on Thursday a day after the Federal Reserve kept interest rates unchanged, while investors assessed a flurry of corporate earnings reports.
The central bank, in a statement following a two-day policy meeting on Wednesday, indicated the economy was growing moderately and job gains had been solid.
However, it noted that both overall inflation and a measure of underlying price gains had declined and said it would "carefully monitor" price trends.
The statement was perceived as dovish by investors, with rate futures pricing in a 38 percent chance of an interest rate hike by December, compared with a little over 50 percent chance priced in before the meeting.
Wall Street closed at record highs on Wednesday, propelled by strong quarterly earnings.
Earnings of S&P 500 companies are now expected to have climbed 9.9 percent in the second quarter, up from a projection of an 8 percent rise at the start of the month, according to Thomson Reuters I/B/E/S.
With equity markets at record levels, investors have been counting on strong earnings to justify the relatively expensive stock valuations.
"Earnings season has arguably taken on additional importance this quarter due to the inability of Donald Trump to, so far, deliver on the growth agenda that won him the White House back in November," said Craig Erlam, senior market analyst at online forex broker Oanda.
"Even in the absence of tax cuts and fiscal stimulus, corporate America has continued to perform well, with companies exceeding expectations on both the top and bottom line."
Dow e-minis were up 13 points, or 0.06 percent, with 21,396 contracts changing hands at 8:35 a.m. ET (1235 GMT).
S&P 500 e-minis were up 4.25 points, or 0.17 percent, with 145,487 contracts traded.
Nasdaq 100 e-minis were up 42.5 points, or 0.71 percent, on volume of 31,063 contracts.
Online giant Amazon, Intel, Starbucks and Mattel are among the major companies reporting results after the bell.
Shares of Facebook jumped 7.23 percent in premarket trading after the social network's results beat Wall Street estimates.
Twitter was down 9.84 percent after the company's quarterly results showed it failed to add users on a monthly basis in the second quarter, compared with the first quarter.
Comcast was up 2.54 percent as its quarterly results topped expectations.
Procter & Gamble rose 2.41 percent, while Mastercard was up 1.61 percent after posting strong quarterly results.
Economic data showed durable goods orders rose more than-expected in June, while weekly jobless claims rebounded from a three-month low last week. (Reporting by Tanya Agrawal in Bengaluru; Editing by Anil D'Silva)