Exact width input fields & text padding conundrum

What's the best solution for wanting exact width input fields (text), where you stipulate the padding too? Cross browser? I've never quite found the best way to 开发者_如何学Godo this. Any thoughts?

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I like Nathan Smith's Formalize, cross browser forms are a complete pain, this really helps: http://formalize.me/

It's mostly CSS but has a bit of JS to make older IEs play nice.