Without some notion of how much your equity grant represents of the company (by current dilution), the actual number of options you get cannot be sensibly valued. The total number of shares at a company is totally arbitrary. Seriously, when you register one, the state just asks you to pick a number.
If a company won't tell you enough to calculate the percentage, that's like you asking "What's your offer for salary?", "Dollars. Definitely dollars.", "Can you be more specific?", "No. We consider exact salary offers to be competitively sensitive."
If a company won't tell you enough to calculate the percentage, that's like you asking "What's your offer for salary?", "Dollars. Definitely dollars.", "Can you be more specific?", "No. We consider exact salary offers to be competitively sensitive."