Crown Prosecution Service (CPS) policy statements have been updated to take account of the mounting number of cases sparked by abuse in cyber space.
The revised documents cover different strands of hate crime - racist and religious; disability; and homophobic, biphobic and transphobic.
They say: " Hate crime can be perpetrated online or offline, or there can be a pattern of behaviour that includes both.
"The internet and social media in particular have provided new platforms for offending behaviour."
The CPS says it will prosecute complaints of hate crime online "with the same robust and proactive approach used with offline offending, whilst recognising that children may not appreciate the potential harm and seriousness of their communications" and "t reat online complaints as seriously as offline complaints".
Prosecutors should also understand the changing nature of platforms and their policies for taking down material, while being alert to the need to identify "originators" as well as "amplifiers or disseminators", according to the documents.
The presence of hateful content on social media sites has repeatedly been highlighted and co mmunity groups monitoring anti-Semitic and Islamophobic abuse report that a significant proportion of incidents involve the internet.
The CPS emphasised that it has always considered each case on its individual merits and prosecutes offences, whether committed online or offline, where there is sufficient evidence and it is in the public interest.
Elsewhere, the policy documents acknowledge that victims of biphobic hate crime have different experiences and needs to those affected by homophobic and transphobic offences.
The CPS also said it recognises it has a responsibility to actively remove barriers to justice for disabled victims and witnesses.
Alison Saunders, the Director of Public Prosecutions, said: "Hate crime has a corrosive effect on our society and that is why it is a priority area for the CPS.
"It can affect entire communities, forcing people to change their way of life and live in fear.
"These documents take account of the current breadth and context of offending to provide prosecutors with the best possible chance of achieving justice for victims.
"They also let victims and witnesses know what they should expect from us."
The authorities' response to hate crime has come under close scrutiny in the last year amid jumps in the number of incidents.
There was a surge in reports following the EU referendum in June 2016, while figures released earlier this month show forces registered a spike around the terrorist attacks that hit the UK earlier this year.
In 2015/16 the CPS completed a record 15,442 hate crime prosecutions.
The conviction rate across all strands of hate crime increased from 82.9% in 2014/15 to 83.2% in 2015/16.
Writing in the Guardian, Ms Saunders said there were "huge questions" over how to counter the airing of extremist views but "no straightforward answers".
She said: "For many people in the UK, the scenes in Charlottesville last weekend may appear to be of scant relevance to their own lives. Even Thursday's horrific events in Barcelona may feel somewhat distant.
"But we should remember that there is a less visible frontline which is easily accessible to those in the UK who hold extreme views on race, religion, sexuality, gender and even disability.
"I refer to the online world where an increasing proportion of hate crime is now perpetrated.
"And this is why the Crown Prosecution Service today commits to treat online hate crimes as seriously as those committed face to face."