Try this tool..Rank Tracker - track your search engine rankings easily!

serplab is pretty useful.

I hope that isn't for one site. If it is, why bother with so many keywords? Just focus on the top 50 and use Google's Webmaster tools to see how you rank for other keywords.

As far as a tool, try WhatsMySERP.com It allows for up to 500 keywords for registered users and will keep track of your history. Results come direct from google and the site is free.

I have been using smallseotools.com/keyword-position and SEO book rank checker. But 600+ keywords at once impossible.

For a single site? That would be a very large number to monitor.
Anyway, that would be hard to track though; I don't use a tool because monitoring it manually would be the most accurate for me.

Tracking 600 keywords can take a long time to load on any SEO tool. I suggest you limit your keywords and prioritize only the ones that will bring you a large amount of traffic per month.

I am using SERP tool to check keyword ranking.

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I don't think 600+ keywords are lot

it just depends on how far back you want to check your SERP rankings

once you know your strong and top ranking keywords it helps you know which keywords you need to put more effort into

I would look at a tool based on how far they can research the SERPs for your listings

Big quantity of keywords.I always prefer SERP tool to check keyword ranking,don't know it will check 600+ keywords.

I always use SERP tool to check keyword ranking.