Sending out a Donald Trump-style stream of consciousness on Twitter while you're looking for a job could find you joining the long-term unemployed.

A US survey last year found more than half of managers have decided not to hire based on an applicant's online profile, and in Australia the task of social media vetting can now even be outsourced.

A start-up called The Social Index will analyse and report back on the applicant's online persona.

Company spokeswoman Fiona McLean said the analysis is done with the applicant's consent and it helps determine how they'll fit in an organisation.

"When people are putting online things that are racist or forms of bullying, that can be a problem because that translates quite easily into the workplace," she said.

The top turn-offs:

Social media sanitisation strategy FORTRESS Lock down extreme privacy settings to limit posts only to select family and friends. SEARCH AND DESTROY Trawl through your timeline and posts and delete anything embarrassing or inappropriate. NUKE IT ALL Delete your social media presence completely. A word of warning: Third party platforms like Google, ad companies and your friends' social media may still show your posts. Information provided by CryptoAUSTRALIA.

They're pretty obvious — inappropriate photos or videos; posts related to drinking or drugs; discriminatory or abusive comments; bad-mouthing previous employers or colleagues; and poor communication skills, including spelling.

The US survey found that many employers were also checking up on current employees, with about 25 per cent of those who do check finding a reason to reprimand or fire an employee.

Ms McLean said it was nearly impossible to keep your online life separate from your professional life.

"We have candidates say 'well my Facebook is for private use' and then they've said 'but all my work colleagues and my boss are on there' and I think means you've merged the two," she said.

So what about those party photos?

"I think everyone's had awkward moments and that's pretty easy to rectify. What we look for is how things evolve over time," Ms McLean said.

"So if you're out every night when you're 18 but you're still doing that 12 years later, we'd want to know what's evolved for you."

The legal rights of workers and employers in this area are still emerging.

Australian workers are protected against discrimination based on religious and political views, sexual preference, gender and race.

What if the company's anti-gay marriage?

And you're pro-gay marriage? Or how about if your new company relies on federal government contracts and you oppose their treatment of refugees?

Tips for being a good digital citizen 1. Delete inappropriate comments, photos, videos and posts as well as abusive or discriminatory language 2. Do not bad mouth your old boss or former colleagues 3. Follow or friend relevant industry and career network sites and individuals; network quality beat quantity 4. Get a professional photo 5. Be careful when liking, retweeting or sharing other people's posts as you may be asked why you agreed with them 6. Check your spelling and grammar as clear communication skills will be assessed 7. Stay authentic and positive; show case your awards, volunteer work, team sports, hobbies and experiences Information provided by Fiona McLean from The Social Index.

"I think that would drive a conversation to understand how that view would fit in with the organisation," Ms McLean said.

"It's not that it matters that there are different views, that's always been an important part of the Australian workplace.

"It's how you handle that conversation online and there are times when a candidate might find themselves not selected for a role because the company feels their brand would be at risk."

Reporter Scott McIntyre lost his job at SBS after a series of tweets attacking the ANZAC legacy. His discrimination suit was settled out of court.

Is it time for an audit?

Ms McLean urged people to regularly audit and edit their social media presence.

CryptoAUSTRALIA, which is part of a worldwide movement teaching about privacy on the internet, runs free forums on how to sanitise your social media.

"We have found the sessions are fully booked so we have to repeat them," said Gabor Szathmari, from CryptoAUSTRALIA.

There are three, somewhat limited options for cleansing your online profile: locking down extreme privacy settings; going back through posts and deleting anything compromising or embarrassing; or "nuking" your social media presence entirely.

And that may count against you. The US employer survey showed that 40 per cent of hiring managers were less likely to interview a candidate if they had no social media presence.

Ms McLean said an active and positive online profile is a bonus for employers especially if a candidate is well connected in relevant industries.

"We're looking at how you're able to create action and engagement in your network. That's a good indication of being a team player or a good leader or both," she said.