Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in Registration Statement Nos. 333-228584 and 333-234764 on Form S-3, and Registration Statement Nos. 333-188552, 333-215798, 333-228637, and 333-235671 on Form S-8 of Diamondback Energy, Inc., of our report dated February 24, 2021, relating to the financial statements of QEP Resources, Inc. incorporated by reference in this Current Report on Form 8-K of Diamondback Energy, Inc. from the Annual Report on Form 10-K of QEP Resources, Inc. for the year ended December 31, 2020. We also consent to the reference to us under the heading “Experts” in such Registration Statements.

Exhibit 23.2

CONSENT OF RYDER SCOTT COMPANY, L.P.

As independent petroleum engineers, we hereby consent to the incorporation by reference in Registration Statement Nos. 333-228584 and 333-234764 on Form S-3, and Registration Statement Nos. 333-188552, 333-215798, 333-228637 and 333-235671 on Form S-8 of Diamondback Energy, Inc. (“Diamondback”), of our appraisal report relating to the proved gas and oil reserves of QEP Energy Company incorporated by reference in this Current Report on Form 8-K of Diamondback from the Annual Report on Form 10-K of QEP Resources, Inc. for the year ended December 31, 2020. We also consent to the reference to us under the heading “Experts” in such Registration Statements.

Denver, Colorado

March 17, 2021

Exhibit 99.1

Diamondback Energy, Inc. Completes Acquisition of QEP Resources, Inc.

Midland, TX (March 17, 2021)—Diamondback Energy, Inc. (NASDAQ: FANG) (“Diamondback” or the “Company”) today announced that it has completed its previously announced acquisition of QEP Resources, Inc. (NYSE: QEP) (“QEP”) in an all-stock merger following approval of the merger and related proposals by the QEP stockholders at their special meeting held on March 16, 2021.

QEP reported the results of its stockholder vote at the special meeting on its Form 8-K with the Securities and Exchange Commission on March 16, 2021.

As previously announced, in the merger, QEP stockholders will receive 0.05 of a share of Diamondback common stock for each share of QEP common stock issued and outstanding immediately prior to the effective time of the merger, with cash to be received in lieu of any fractional shares. As a result of the merger, QEP common stock will no longer be listed for trading on NYSE and its reporting obligations under the Securities Exchange Act of 1934 will be suspended.

“We are excited to announce that we have completed our acquisition of QEP. This deal, along with our recently completed acquisition of certain assets from Guidon Operating LLC (the “Guidon acquisition”) bolsters our depth of Tier 1 Midland Basin inventory and positions us to allocate a majority of our capital to the high-returning Midland Basin for the foreseeable future. We look forward to updating the market on our progress on synergy capture and laying out the pro forma operating plan for 2021 as soon as practicable,” stated Travis Stice, Chief Executive Officer of Diamondback.

About Diamondback Energy, Inc.

Diamondback is an independent oil and natural gas company headquartered in Midland, Texas focused on the acquisition, development, exploration and exploitation of unconventional, onshore oil and natural gas reserves primarily in the Permian Basin in West Texas. For more information, please visit www.diamondbackenergy.com.

Forward-Looking Statements

This news release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements, other than historical facts, that address activities that Diamondback assumes, plans, expects, believes, intends or anticipates (and other similar expressions) will, should or may occur in the future are forward-looking statements. The forward-looking statements are based on management’s current beliefs, based on currently available information, as to the outcome and timing of future events, including the current adverse industry and macroeconomic conditions, commodity price volatility, production levels, the impact of the recent presidential and congressional elections on energy and environmental policies and regulations, any other potential regulatory actions (including those

that may impose production limits in the Permian Basin), the impact and duration of the ongoing COVID-19 pandemic, acquisitions and sales of assets (including the recently completed Guidon acquisition and the merger discussed in this news release and anticipated synergies), future dividends, production, drilling and capital expenditure plans, severe weather conditions (including the impact of the recent severe winter storms on production volumes), impact of impairment charges and effects of hedging arrangements. These forward-looking statements involve certain risks and uncertainties that could cause the results to differ materially from those expected by the management of Diamondback. Information concerning these risks and other factors can be found in Diamondback’s filings with the Securities and Exchange Commission (“SEC”), including its reports on Forms 10-K, 10-Q and 8-K, which can be obtained free of charge on the SEC’s web site at http://www.sec.gov. Diamondback undertakes no obligation to update or revise any forward-looking statement.

Investor Contact:

Adam Lawlis

+1 432.221.7467

alawlis@diamondbackenergy.com

Exhibit 99.2

UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL STATEMENTS

On March 17, 2021, Bohemia Merger Sub, Inc. (“Merger Sub”), which is a direct, wholly owned subsidiary of Diamondback Energy, Inc. (“Diamondback”), completed its previously announced merger with QEP Resources, Inc. (“QEP”), pursuant to the Agreement and Plan of Merger, dated as of December 20, 2020 (the “merger agreement”), by and among Diamondback, Merger Sub and QEP. Pursuant to the merger agreement, Merger Sub merged with and into QEP (the “merger”), with QEP continuing as the surviving corporation and as a direct, wholly owned subsidiary of Diamondback. At the effective time of the merger (the “effective time”), each eligible share of QEP common stock (other than (i) shares held in treasury by QEP, (ii) shares owned by Diamondback or Merger Sub and, in each case, not held on behalf of third parties and (iii) certain shares of QEP common stock subject to the applicable QEP stock-based award agreements) issued and outstanding immediately prior to the effective time converted into the right to receive 0.050 of a share of Diamondback common stock (the “exchange ratio”), with cash being paid in lieu of any fractional shares (the “merger consideration”).

The following unaudited pro forma condensed combined financial information (the “pro forma financial statements”) gives effect to the merger, which will be accounted for using the acquisition method of accounting, with Diamondback identified as the acquirer. Under the acquisition method of accounting, Diamondback will record assets acquired and liabilities assumed from QEP at their respective acquisition date fair values at the effective time.

The pro forma financial statements have been prepared from the respective historical consolidated financial statements of Diamondback and QEP, adjusted to give effect to the merger. The unaudited pro forma condensed combined balance sheet (the “pro forma balance sheet”) combines the historical condensed consolidated balance sheets of Diamondback and QEP as of December 31, 2020, giving effect to the merger as if it had been consummated on December 31, 2020. The unaudited pro forma condensed combined statement of operations (the “pro forma statement of operations”) combines the historical consolidated statements of operations of Diamondback and QEP for the year ended December 31, 2020, giving effect to the merger as if it had been consummated on January 1, 2020. The pro forma financial statements contain certain reclassification adjustments to conform the historical QEP financial statement presentation to Diamondback’s financial statement presentation.

The pro forma financial statements are presented to reflect the merger and do not represent what the combined company’s financial position or results of operations would have been had the merger occurred on the dates noted above, nor do they project the financial position or results of operations of Diamondback following the merger. The pro forma financial statements are intended to provide information about the continuing impact of the merger as if it had been consummated earlier. The pro forma adjustments are based on available information and certain assumptions that management believes are factually supportable and are expected to have a continuing impact on Diamondback’s results of operations, with the exception of certain non-recurring charges to be incurred in connection with the merger, as further described below. In the opinion of management, all adjustments necessary to present fairly the pro forma financial statements have been made.

Diamondback and QEP have incurred, or will incur, certain non-recurring charges in connection with the merger, the substantial majority of which consist of employee retention costs, fees paid to financial, legal and accounting advisors, severance and benefit costs, and filing fees. Any such charge could affect the future results of the combined company in the period in which such charges are incurred; however, these costs are not expected to be incurred in any period beyond 12 months from the closing date of the merger. Accordingly, the pro forma statement of operations for the year ended December 31, 2020 reflects the effects of these non-recurring charges, to the extent such costs are not included in the historical balance sheets of Diamondback or QEP as of December 31, 2020.

While the pro forma financial statements do not include the realization of any cost savings from operating efficiencies, synergies or other restructuring activities which might result from the merger, management’s estimates of certain cost savings to be realized following closing of the merger are illustrated in Note 4 to the pro forma financial statements. Further, there may be additional charges related to the restructuring or other integration activities resulting from the merger, the timing, nature and amount of which management cannot identify as of this date. Thus, such charges are not reflected in the pro forma financial statements.

The pro forma purchase price allocation is preliminary and was based on estimates of the fair market values of the assets and liabilities of QEP as of March 9, 2021. The assumptions and estimates used to determine the preliminary purchase price allocation and fair value adjustments are described in the notes accompanying the pro forma financial statements. The preliminary pro forma adjustments have been made solely for the purpose of providing the pro forma financial statements presented below.

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The value of the consideration paid by Diamondback at the closing of the merger has been determined based on the closing price of Diamondback’s common stock on the closing date of the merger. The final determination of fair market value will be based on the identifiable assets acquired and liabilities assumed of QEP that existed as of the closing date of the merger. The final purchase price allocation for the business combination will be performed subsequent to closing and adjustments to estimated amounts or recognition of additional assets acquired or liabilities assumed may occur as more detailed analyses are completed and additional information is obtained about the facts and circumstances that existed as of the closing date of the merger. Any increases or decreases in the fair value of assets acquired and liabilities assumed upon completion of the final valuation will result in adjustments to the pro forma balance sheet and, if applicable, the pro forma statement of operations. Diamondback expects to finalize the purchase price allocation as soon as practicable after completing the merger.

The final purchase price allocation may be significantly different than that reflected in the preliminary purchase price allocation presented herein. As a result of the foregoing, the pro forma adjustments are preliminary and subject to change as additional information becomes available and additional analysis is performed.

The pro forma financial statements have been developed from and should be read in conjunction with the accompanying notes to the pro forma financial statements, as well as the separate historical consolidated financial statements and related notes thereto in each of Diamondback’s and QEP’s filings with the Securities and Exchange Commission (“SEC”).

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DIAMONDBACK ENERGY, INC. AND SUBSIDIARIES

UNAUDITED PRO FORMA CONDENSED COMBINED BALANCE SHEET

As of December 31, 2020

See accompanying “Notes to the Unaudited Pro Forma Condensed Combined Financial Statements”

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DIAMONDBACK ENERGY, INC. AND SUBSIDIARIES

UNAUDITED PRO FORMA CONDENSED COMBINED STATEMENT OF OPERATIONS

For the Year Ended December 31, 2020

See accompanying “Notes to the Unaudited Pro Forma Condensed Combined Financial Statements”

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NOTES TO UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL STATEMENTS

NOTE 1 – BASIS OF PRESENTATION

The Diamondback and QEP historical financial information has been derived from each respective company’s Annual Report on Form 10-K for the year ended December 31, 2020. Certain of QEP’s historical amounts have been reclassified to conform to Diamondback’s financial statement presentation, as discussed further in Note 3. The pro forma financial statements should be read in conjunction with Diamondback’s and QEP’s historical audited consolidated financial statements and the notes thereto included in their respective Annual Reports on Form 10-K for the year ended December 31, 2020. The pro forma balance sheet gives effect to the merger as if it had been completed on December 31, 2020. The pro forma statement of operations gives effect to the merger as if it had been completed on January 1, 2020.

The merger and the related adjustments are described in the accompanying notes to the pro forma financial statements. In the opinion of Diamondback’s management, all material adjustments have been made that are necessary to present fairly, in accordance with Article 11 of Regulation S-X, the pro forma financial statements. The pro forma financial statements do not purport to be indicative of what the combined company’s financial position or results of operations would have been if the merger had occurred on the dates indicated, nor are they indicative of Diamondback’s future financial position or results of operations.

NOTE 2 – PRELIMINARY ACQUISITION ACCOUNTING

Diamondback has determined it is the accounting acquirer in the merger, which will be accounted for under the acquisition method of accounting for business combinations in accordance with Accounting Standards Codification 805, Business Combinations (“ASC 805”). The allocation of the preliminary estimated purchase price with respect to the merger of approximately $976 million is based upon management’s estimates of, and assumptions related to, the fair values of assets to be acquired and liabilities to be assumed as of December 31, 2020, using information available as of March 9, 2021. Due to the fact that the pro forma financial statements have been prepared based on these preliminary estimates, the final purchase price allocation and the resulting effect on Diamondback’s financial position and results of operations may differ significantly from the pro forma amounts included herein.

The final purchase price allocation for the business combination will be performed subsequent to closing and adjustments to estimated amounts or recognition of additional assets acquired or liabilities assumed may occur as more detailed analyses are completed and additional information is obtained about the facts and circumstances that existed as of the closing date of the merger. Diamondback expects to finalize the purchase price allocation as soon as practicable after completing the merger.

The preliminary purchase price allocation is subject to change due to several factors, including, but not limited to:

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The following table presents the preliminary merger consideration and preliminary purchase price allocation of the assets acquired and the liabilities assumed in the merger:

The final value of the merger consideration to be paid by Diamondback will be determined based on the actual number of shares of Diamondback common stock issued and the market price of Diamondback’s common stock at the closing date of the merger. A 15% increase or decrease in the closing price of Diamondback’s common stock, as compared to the March 9, 2021 closing price of $81.03, would have increased or decreased the merger consideration by approximately $147 million, assuming all other factors are held constant.

NOTE 3 – PRO FORMA ADJUSTMENTS

The pro forma financial statements reflect reclassifications of QEP’s financial statements to conform to Diamondback’s financial statement presentation and adjustments to QEP historical book values to reflect their preliminary estimated fair values in accordance with the acquisition method of accounting, the estimated closing price to be paid by Diamondback for the common stock of QEP, estimated direct transaction costs, and the estimated tax impacts of pro forma adjustments. These adjustments:

Pro Forma Balance Sheet as of December 31, 2020:

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Pro Forma Statement of Operations for the year ended December 31, 2020:

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NOTE 4 – MANAGEMENT’S ADJUSTMENTS

Management expects that, following the closing of the merger, the post-acquisition company will realize certain cost savings as compared to the historical combined costs of Diamondback and QEP operating independently. Management’s adjustments, which are based on estimated cost savings as a result of the integration of personnel and the manner in which the post-acquisition company will be integrated and managed prospectively, are not reflected in the pro forma statement of operations. Management expects that the merger will result in approximately $60 million to $80 million in annual cost savings, primarily related to general and administrative synergies, as well as certain capital efficiencies that are not reflected in the table below. The cost savings from such synergies over the life of the properties are expected to be between approximately $500 million and $700 million in present value (at a 10% discount factor).

Limitations of these adjustments include not fully realizing the anticipated benefits, taking longer to realize the expected cost savings, or other adverse effects that Diamondback does not currently foresee. Further, Diamondback may incur additional charges in achieving these expected cost savings that are unknown in nature and amount as of the closing date. Thus, such charges are not reflected in the pro forma statement of operations. The pro forma financial information only includes adjustments that are, in the opinion of management, necessary to a fair presentation of such information. Future results may vary significantly from the pro forma financial information presented.

Had the merger been completed as of January 1, 2020, management estimates that general and administrative expenses of $70 million, on a pre-tax basis, would not have been incurred by the combined company for the year ended December 31, 2020.

The tax effect of the aforementioned adjustments has been calculated based on the blended federal and state statutory rates applicable to such adjustments of approximately 21.6%.

The following table presents the estimated effects on the pro forma statement of operations of the elimination of the identified expenses:

NOTE 5 – SUPPLEMENTAL PRO FORMA OIL AND NATURAL GAS RESERVES INFORMATION

The following tables present estimated pro forma combined oil and natural gas reserves information as of and for the year ended December 31, 2020. The amounts below were determined based on the amounts reported in Diamondback’s and QEP’s respective Annual Reports on Form 10-K for the year ended December 31, 2020. An explanation of the underlying methodology applied, as required by SEC regulations, can be found within the respective Annual Reports on Form 10-K. The following estimated pro forma combined oil and gas reserves information is not necessarily indicative of the results that might have occurred had the merger been completed on December 31, 2020 and is not intended to be a projection of future results. Future results may vary significantly from the results presented.

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Oil and Natural Gas Reserves

The following tables present the estimated pro forma combined net proved developed and undeveloped oil and gas reserves information as of December 31, 2020, along with a summary of changes in quantities of net remaining proved reserves during the year ended December 31, 2020:

Standardized Measure of Discounted Future Net Cash Flows

The following table presents the pro forma combined standardized measure of discounted future net cash flows relating to proved oil and natural gas reserves as of December 31, 2020:

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Sources of Change in Discounted Future Net Cash Flows

The principal changes in the pro forma combined standardized measure of discounted future net cash flows relating to proved reserves for the year ended December 31, 2020 are as follows:

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