2 Answers
Accepted answer

Actually, the PeerJ plans are 'good for life', meaning that a single payment of as little as $99 means that an individual can publish 1 paper per year, for life, with PeerJ.

In addition, PeerJ caps the number of co-authors who need to pay at 12 . Therefore even if you had a 13 (or more) co-authors on a paper (which is extremely rare), the charge for their first paper (and remember that all subsequent papers are free) would be just 12x$99 which is still a lot cheaper than journals such as PLOS ONE ($1,350) or Nature Communications ($5000) for example, and at PeerJ you get for superior service.

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