A directional timeline range, not a quote. Enter your approximate lines of code and see what one documented real-world conversion suggests for scale.
1 to 2 months
For a full automated-conversion rewrite of roughly 500,000 lines. This scales linearly off the one case we have data for, which is a real limitation: treat it as an order-of-magnitude check, not a plan.
For an actual estimate, talk to a vendor who does this for the language you're working with. Find one →