Ira Kaminow, like many people, finds himself deluged by requests from charities seeking donations. "I am on the receiving end of 200 solicitations a year," he says.

A discriminating donor, Kaminow likes to investigate carefully before handing over his dollars. After accumulating information on Jewish charities for years, the Potomac, Md., economist has started a Web site to help other donors do the same.

Kaminow says the site — www.just-tzedakah.org — is aimed at increasing the level and effectiveness of tzedakah among American Jews. It details the backgrounds, missions, religious observance, personnel, salaries and finances of about 50 national Jewish and Israeli charities. More reports are on the way.

The site also includes information on the Jewish view of tzedakah — when to give, how to give, how much to give and to whom. A section titled "What Our Sages Say" offers quotes and stories from Jewish texts on such topics as fraud, tithing and the ethics of investigating the needy who ask for tzedakah.

As it turns out, Jewish tradition encourages those who dispense charity to investigate whether supplicants are worthy recipients, at least in some cases.

The Web site, of course, goes a step further, investigating the organizations collecting money for the needy. But Kaminow, visiting San Francisco last week, stressed that donors need to make their own determinations on what makes a charity worthy of their dollars.

"I don't interpret the information," he says. "My advice is always to find out what you personally feel is important in making an evaluation. It all depends on what criteria the individual values."

For example, some may prefer to donate to an organization whose top officials volunteer their time rather than one whose officials command top dollars. Others may like to check out who endorses a charity or which, if any, awards it has received. Kaminow's reports on the charities include such information.

The site also tries to help prospective donors determine whether a charity is meeting its stated objectives for doling out funds.

A policy consultant working in Washington, Kaminow acknowledges that a copious amount of time goes into making his site run. He loves doing it. "It has become both a hobby and a passion."

Before launching his Web site more than a year ago, Kaminow, who is 59 and Orthodox, published Tzedakah Reports, a compilation of information on Jewish charities. He is currently in the process of transferring more of those reports onto the Web and updates the information regularly.

Among organizations already detailed on the site are such well-known entities as Hadassah, American Friends of Hebrew University, the Anti-Defamation League and Mazon: A Jewish Response to Hunger. Others include New Israel Fund, Jewish Braille Institute of America and North American Conference on Ethiopian Jewry.

Compiling information for his extensive site, Kaminow says, has made him more careful about his own charitable decisions. "I no longer give to organizations that will not tell me what they do with the funds."