How can I determine whether a conference is reputable?

Note: This answer was merged from a duplicate question.

The previously-referenced post on detecting predatory journals is helpful, but incomplete. The duplicate question asked about conferences which were overt about accepted papers being able to be published in conference proceedings with an ISBN. While I cannot speak for all fields, I can say that in social sciences and statistics, that description alone sounds like a low-quality conference.

In my experience, there are a few markers ("red flags") for low-quality conferences. This list is by no means canonical, but is based on over a decade of my experience.

The first red flag is the note that accepted papers will be published in conference proceedings with an ISBN or ISSN number. Sure, some very good conferences allow for dual submission to a journal or a journal publishes conference proceedings. However, the explicit mention of an ISBN number (often required by accreditors for a professor to remain academically qualified) is something I have seen only at low-quality conferences. Good conferences know that you may want to publish your work elsewhere and assume you are not desperate for any publication. (Caveat: Some fields like engineering tend to publish their work more as conference papers or in proceedings. In those cases, the overt mention of publishing in proceedings may not be a red flag.)

The second red flag is when a conference folds many costs into a high registration fee. This can let dishonest academics claim a food per diem while the "registration fee" can be paid out of a research budget even though that fee also covers food and parties. I'm not talking about a $150 fee; rather, I have seen conferences with a $750 or $1000 fee which covers swanky parties. Most serious researchers getting their work into more than a couple of conferences won't want to blow their research budget on one conference with a bunch of parties. (Besides, most academics can make party enough talking with other academics over some wine or beer.)

The third red flag is the conference's call for papers: if they spam people with the CFP and the deadline does not allow much time for review, that's likely a low-quality conference.

A fourth red flag is if the conference has an unusually broad focus. Some big conferences may cover a wide range of topics; however, you probably already know the reputable big conferences which do that. Less well-known conferences tend to be more focused.

A fifth red flag is if the conference is held in a nice and unusual place. Sure, lots of conferences are in nice places to attract academics, but I'm talking about unusual places like a conference on a cruise ship or a tropical island with no local university. If there is no local academic community organizing the conference, the expected quality is lower.

Suppose a conference does not raise any (or many) of these red flags. How can further check the quality? Usually, this is easy: see who the organizers are and look for prior year agendas to see if there are many good academics presenting (or people from industry/government, in some fields). Essentially, check if the organizers and presenters are people you would want to see and comment on your work. If those people are there, you probably also should want to be there. If none of the names are familiar, you may want to consider if that is a good outlet for getting feedback.

Finally, you ask if you can submit your work to the proceedings and then later extend the work and submit it to a journal. Sadly, that depends on the journal and I do know of people who were told their work could not be accepted since most of it had been published earlier in conference proceedings.

In addition to the other answers, it's worth taking a close look at conferences that tick several of these boxes (although some may turn out to be OK on further inspection). These can be warning signs of conferences that are basically scams, or that will be a waste of your time/money/energy.

Items 2-5 are indicators of insufficient peer review, and are problematic only for conferences that claim to publish peer-reviewed proceedings.

Items 6-9 are warning signs that the aim of the conference organizers is profits, not academics.

1. Organizers, program committee members, or keynote speakers are not established researchers in the field (as per some of the other answers on this page).
2. It has an extremely short review period (e.g. submissions due November 1, author notification November 10).
3. You receive reviews that are very short and/or don't say anything insightful about the paper.
4. The technical program committee is small, but the conference accepts hundreds of papers.
5. If the conference proceedings are published or indexed by a well-known publisher, look at past editions of the proceedings and check if multiple papers have been retracted or withdrawn for plagiarism and/or for being computer generated.
6. The scope of the conference is extremely broad, such that people who work in one of the areas of interest are not likely to be interested in presentations from the other areas (this can be a tactic to get a lot of submissions, at the expense of conference quality).
7. The conference organizer also organizes many other conferences, on a very diverse range of unrelated topics.
8. The organizer holds many conferences on unrelated topics at the same time and place.
9. The organizer is also associated with one or more predatory journals, or selected papers from the conference are published in a predatory journal.

Looking at the program committee, organizers, other presenters (e.g. keynote speakers) and what work they've done is one helpful approach. Asking your advisor is often quite useful.

Also consider if you've read papers from that venue in the past and found them helpful enough and high-quality enough to be citing / using as a basis for your work.

Finally, there's the Computing Research & Education conference ranking portal here which might be another signal to consider.

Maybe I will add to JeffE’s answer. I agree with him that, in your field, you probably have established your own list of reputable conferences after a few years. However, it does happen that you get invited or submit a paper to a conference that's outside your natural “comfort zone”. One reason is because of a joint work with other authors from that area, another may be that you are shifting the focus of your research, or you published a paper that has potential applications in another field.

Anyway, if that happens, you want to check out the organizers and speakers (keynote speakers if it's a large conference). One or two serious people doesn't mean anything though, especially if the conference is held in an attractive touristic area (Caribbean islands?). Some people accept conferences that they know are not good, if they see a nice opportunity for a holiday in them. However, if half the organizers or speakers are well known, or have well established research groups, then you're probably good to go.

What I usually do is look at the list of speakers in the current and past years. If the conference is in my field, I usually can tell if the speakers are well-known and what the level of the conference will be. If the conference is not in my field, I google some of the speakers and check out their websites to get an impression.

Another thing which is often helpful to do, is to simply ask someone with knowledge of the field which conferences are good.

I'm assuming you are really asking how to check whether a conference is reputable (meaning not a scam), not how to check whether a conference is actually good.

Short answer: If you don't recognize the conference or its organizers, stay away.

You should already know a relatively short list of established, reputable conferences in your research area. If you don't, ask your advisor to give you such a list. (If your advisor doesn't know, you need a new advisor.)

If this conference isn't on that list, it might still be reputable, but either very new or slightly outside your research area. In that case, take a serious look at the organizing committee. If the members of the organizing committee are well-known active researchers, the conference is probably fine. Otherwise, it's probably a scam.

You mention that you were invited to submit to the conference. At least in computer science, such invitations are almost unheard of; conferences are normally advertised by impersonal calls for papers. Did the invitation come from someone you already know, at least professionally? Does the invitation mention specific technical details of your work (more than just a paper title)? If you answered "No" to both these questions, the conference is almost certainly a scam.