One minute of arc is 1/60 of 1°

One second of arc is 1/60 of one minute of arc, or 1/3600 of 1°.

Are you sure they use seconds and minutes in angle calculation? I mean, are there two ways of doing it or something?

I haven't looked for it at this site's calculator, but most likely you have to be content with fractions of degrees. 

I'll go and check now .....

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If you have, say, D degrees M minutes and S seconds, enter this as D + M/60 + S/3600

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