He told the BBC that including Budget measures, the top 10% of earners would be hit hardest but everyone was making a contribution to cutting the deficit.
He said "the path to economic ruin" lay ahead if the deficit was not tackled.
Labour called the £81bn cuts - the biggest since the 1970s - a "reckless gamble" with the economy.
It has been estimated that the measures will lead to the loss of 490,000 public sector jobs, but Mr Osborne told BBC Breakfast he expected many more private sector jobs to be created over the four year cuts programme.
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The Spending Review: Making It Clear
* Key points at-a-glance
* In quotes: Reaction
* Analysis: Impact still unclear
* Video and text: Speech in full
Mr Osborne told MPs on Wednesday that he had acted to restore "sanity to our public finances" and deal "decisively" with Britain's record peacetime deficit.
The government says public debt interest repayments now total £120m a day, or £43bn a year.
Hours after Mr Osborne's speech, crowds of demonstrators gathered outside Downing Street to protest against the cuts, which the TUC has said will have a devastating social impact.
Mr Osborne is currently in the midst of a round of interviews explaining his decisions in the Spending Review which, according to the Institute for Fiscal Studies (IFS) think tank, represent the deepest six-year period of cuts since the 1970s - not since World War II as previous plans implied.
The chancellor said he had been able to restrict departmental spending cuts to an average of 19% over four years - not the 20% he said Labour had planned - because of "tough but fair decisions to reform welfare, and the savings we've made on debt interest". He unveiled plans to cut a further £7bn from the welfare budget - on top of £11bn cuts already announced - which include putting a time limit on some incapacity benefits and changes to tax credits and housing benefit.
He also announced that the state pension would rise to 66 for both men and women in 2020 - six years earlier than planned - and there would be a £3.5bn increase in public sector employee pension contributions.
These plans were unveiled alongside other changes, including a permanent bank levy, tax changes and cuts to child benefit for higher earners.
Mr Osborne said "those with the broadest shoulders should bear the greatest burden. Those with the most should pay the most, including our banks".
Banks will find out later how a new levy on their finances will operate.
However, Labour said the Treasury's own figures showed that the poorest 10% of people would pay more to reduce the deficit than everyone other than the richest 10%.
'State retreating'
Shadow chief secretary to the Treasury Angela Eagle told BBC Two's Newsnight: "What we have got here is not actually a blueprint for recovery, it is not actually a plan for a big society.
"When you look at it, it is the state retreating. It is a blueprint for a smaller, meaner and nastier society and we think the government has got it wrong."
Shadow Chancellor Alan Johnson, who labelled the cuts a "reckless gamble with people's livelihoods", said there were "serious unanswered questions on how many jobs will be lost and how much the redundancies will cost the taxpayer". IFS acting director Carl Emmerson told Channel 4 News: "The benefit cuts we heard about today - an extra £7bn - on average will impact those in the bottom half of the income distribution more than the top half of the income distribution. Therefore, they are regressive."
He added that the best estimate suggested that the poorest 50% would also be hit harder by public service cuts.
The IFS also suggested it was still "quite possible" that the chancellor would have to make further spending cuts or put up tax in order to meet his target for tackling the deficit - if it turns out to be larger than the official estimate.
However, the Fitch ratings agency said Mr Osborne's measures should help the UK retain its prized triple A credit rating.
Mr Osborne said the cuts were guided by fairness, reform and growth: "There have been some difficult decisions on welfare, but I have sought to protect the most vulnerable and I think our overall welfare reforms will help give incentives to many in our country who currently don't have them to seek employment."
The main new welfare savings come from abolishing Employment and Support Allowance, which replaces incapacity benefit, for some categories of claimant after one year, raising £2bn.
Universal benefits for pensioners will be retained, as budgeted for by the previous government, and the temporary increase in the cold weather payment will be made permanent.
