Shares of the Cleveland company at last check fell 1.4% to $16.81.
Cleveland-Cliffs earned $41 million, or 7 cents a share, in the quarter compared with a loss of $52 million, or 18 cents a share, in the year-ago period.
Revenue reached $4.05 billion from $359 million a year earlier.
“Q1 was just the first full quarter for Cleveland-Cliffs as a fully transformed business, and we have already accomplished a lot," Chairman, President and Chief Executive Lourenco Goncalves said in a statement.
"This being said, and with all the operational and commercial actions we have been implementing, the best will come through during the balance of 2021," added Goncalves.
The company also raised a profitability metric for 2021 based on better-than-expected contract renewals and also the assumption that the U.S. hot-rolled-coil index price averages $1,100 per net ton for the last nine months of the year.
Cleveland-Cliffs expects full year adjusted earnings before interest, taxes, depreciation and amortization of $4 billion, up $500 million from its guidance of roughly $3.5 billion.
Goncalves said "the pricing environment we are in -- and will continue to benefit from going forward -- is not a consequence of luck."
"Our expectation of $4 billion in adjusted Ebitda for the full year is predicated on conservative pricing expectations relative to today’s pricing and the current forward curve.
"This will allow us to generate record levels of free cash flow and pay down a substantial amount of debt, allowing us to reach leverage of less than 1 times by the end of the year," he added.