The Conservatives want to trial no notice Ofsted inspections, and extend the length of inspections at secondary schools and large primaries to three days, it has been revealed tonight.
The extra day of inspection would be focused on a school's approach to behaviour, bullying and its extra curricular offer, the Tories said.
If the party is elected next month it plans to pilot a no notice inspection scheme where the requirement to notify schools the day before is waived.
Labour: Plan to abolish Ofsted
Conservatives: Funding pledge in manifesto
The Conservatives have also said they would give the inspectorate an extra £10m towards training and deploying more inspectors.
And the party reaffirmed its commitment to end the exemption on outstanding schools being routinely inspected – a plan that was announced before the general election was called.
The Conservatives highlighted the contrast between their plans to extend Ofsted's work with Labour’s plan to scrap the inspectorate.
Education secretary Gavin Williamson said: “Ofsted is an independent and trusted source of information for parents and teachers and their inspections help to raise standards in our schools.
"But Jeremy Corbyn's Labour want to scrap Ofsted, meaning parents won'thave reliable information about the performance of their child's school.
"Without independent inspections school standards would fall and our children would be less safe.
"A Conservative government will back Ofsted with more funding to carry out better and more focused inspections so that parents have more reliable information about their child's school, and school standards are driven up across the country."
Last year Amanda Spielman told Tes that the inspectorate would like to pilot no-notice inspections.
She was responding to a YouGov survey, published by Ofsted, which found that 61 per cent of parents supported unannounced visits.
Ms Spielman is the third chief inspector to consider no notice inspections.
In 2009, the then chief schools inspector, Christine Gilbert abandoned plans because of parental concerns that they would not be able to make their views known before an inspection.
Three years later Sir Michael Wilshaw relented on plans for no-notice inspections after logistical concerns were raised by heads.
Tes revealed earlier this year that Ofsted was planning for inspectors to arrive at schools at 150 minutes notice after a phonecall under its new inspection framework.
But this plan was shelved after negative feedback from schools during a consultation.
In tonight's announcement prime minister Boris Johnson has given Ofsted his backing.
He said: "In the past decade, the hard work of teachers and our school reforms have meant record numbers of children in good or outstanding schools - more children having a good education and learning the knowledge and skills they need to go on and live a fulfilled life."
Labour’s plan to abolish Ofsted is one of the main education pledges in its manifesto.
Tes first revealed that Labour was planning radical reforms on school inspection in June this year.
The party has said Ofsted would be replaced with inspections being transferred to a new body "designed to drive school improvement".
The Liberal Democrats have also pledged to scrap Ofsted, having first announced the policy last year.
Angela Rayner, Labour shadow education secretary, said: “Ofsted is not fit for purpose. It has created a culture of fear among teachers, driven thousands from the profession, and fails to give parents meaningful information about their children’s school.
“Labour will replace Ofsted with a system that empowers parents and teachers, while protecting pupils, ensuring expertise at the heart of every inspection. We’ll ensure that parents receive more information about their child’s school than just a single grade and that teachers are supported to get on with providing all children a high quality education.”