The Dane, who completed 119 laps during testing at Barcelona on Tuesday, has one further day in the new R.S.16 before heading to Melbourne, but feels he already has a good idea of where the team is likely to be in the pecking order.
"I think we're just around the points, maybe just outside, on a good day," he told reporters. "If we can get points in Melbourne, that's a good weekend.
"We're running different tyres [to our rivals]. If you look at the field today, many people were on mediums, some were on softs, so it's difficult to say where we are yet.
"But it does look quite close around the midfield - hopefully it will be really close so we can make a difference."
One of the teams Renault expect to be competing with is Toro Rosso, and Magnussen found himself running behind Max Verstappen at several points on Tuesday – something he indicated had been a valuable learning experience.
"I think it was good to be behind Max for a few laps, because it's not often you get to be in traffic in testing, so it's good to get an idea of how the car feels in ‘dirty air'," he said.
"It's difficult to know what sort of engine setting he is in - you don't know if he's pressing the overtake button or draining his battery or charging - but I was pulling on him on the straights.
"Obviously I hope he was flat out!"
Asked about how the R.S.16 would be developed between now and the first race, Magnussen said that the team are due to trial a new front wing this week but there will be no major developments for Melbourne.
"We can fine tune what we have and there's room for improvement," he said, "but we're doing quite well I think - we've come a long way in the three days that I've been in the car.
"I feel ready for Melbourne. You never feel 100 percent ready but I'd feel happy going into the race now."
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