Can I get an estimate of the Social Security I can collect on my ex-spouse's record?

Yes. A representative at your local Social Security office can provide estimates of the benefit you can receive as a divorced spouse, based on your former wife’s or husband’s earnings record. Call your local office or Social Security's national customer service line (800-772-1213) to make an appointment. 

You’ll need to show your marriage certificate and divorce decree to prove that the union lasted at least 10 years, the basic qualification for ex-spouses to receive benefits. You also have to provide your former spouse’s Social Security number — or, if you don’t have that, his or her date of birth, place of birth and parents’ names — so Social Security can locate the relevant work record. 

Keep in mind

If you’ve remarried, this is probably moot. Except in very limited circumstances, you cannot collect spousal benefits on the record of a living ex-husband or ex-wife if you have wed again.