A 1000 word blog post is much more than a short article. It is an in-depth analysis of a specific topic with the intention of educating the reader. Consequently, it requires more time and effort to produce than a standard article. On average, it takes around 800 words to write a 1000 word blog post.
This means that it will take around 8 hours to write a 1000 word blog post assuming you have no interruptions. Assuming you can write at a consistent pace, it would be advisable to aim for 1000 words instead of 750 words or 500 words, as these shorter posts tend to be less thorough.