Depending on your niche, your job board has a ceiling in terms of how much money it can make.
I have worked with a number of clients over the years who have made money with job boards. But the amount they make depends on a number of factors with the most important being the industry you want to serve and your level of marketing skills.
For instance, an insurance industry news website came to me and we launched a niche board that serves their audience in a few states. They make between $20k-$25 per year in job posting revenue. For them its just a PART of their business, it would never make it as a stand alone one.
- Yet another client who launched a national niche site targeting pet care made $60k in its first year.
- A tech community I know of that also has a job board makes mid six figures.
- A well established job board in the education space that has been online for 10+ years makes $1 million.
- A diversity job board site I know makes $120k per year.
- RemoteOk reportedly made $2 to $3 million at its height.
So you can see it really varies. The smaller your niche the less you will make. Generally speaking, a national site that focuses on a big market (i.e. sales, healthcare, etc) have the biggest upside. While sites that target narrow industries or jobs have a much shorter ceiling in terms of what they can earn.
At the end of the day you still need to be a good marketer to attract both a job seeker and employer audience in order to make money. And it will take time to establish yourself. The first year is not about making money its about establishing your brand and value proposition.