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                                                                   EXHIBIT 10.01

                               AMENDMENT AGREEMENT

     THIS AMENDMENT AGREEMENT (this "Amendment Agreement") is made and entered
into as of November 12, 2001 (the "Effective Date"), by and between Keynote
Systems, Inc., a Delaware corporation (the "Company"), and Umang Gupta
("Executive"). Capitalized terms not defined herein shall have the meanings
ascribed to them in the Original Agreement (as defined below).

                                    RECITALS

     WHEREAS, the Company and Executive are parties to that certain Employment
Agreement made and entered into as of December 9, 1997 (the "Original
Agreement"), pursuant to which the Company employs Executive; and

     WHEREAS, the Company and Executive wish to amend the Employment Agreement
by entering into this Amendment Agreement and Section 10.7 of the Original
Agreement provides that it may be amended by a written agreement executed by
Company and Executive.

     NOW, THEREFORE, in consideration of the foregoing recitals and for other
consideration, the adequacy and sufficiency of which is hereby acknowledged, the
parties hereto hereby agree as follows:

     1.   Amendments to Original Agreement.
          --------------------------------

          1.1  Base Salary. Section 5.1 of the Original Agreement is hereby
               -----------
amended in full on the Effective Date to read as follows:

               "5.1 Base Salary. The Company agrees to pay Employee an annual
                    -----------
               salary of Two Hundred Fifty Thousand Dollars ($250,000.00), or in
               the event of any portion of a year, a pro rata amount of such
               annual salary. Employee's annual salary will be payable as earned
               in accordance with the Company's customary payroll practice.

          1.2  Natural Transition. Section 7.4 of the Original Agreement is
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hereby amended in full to read as follows:

               "7.4 Natural Transition. Company and Employee also wish to
                    ------------------
               provide for their respective rights and obligations should they
               mutually agree to engage Employee in the process of recruiting a
               successor Chief Executive Officer and assisting in that person's
               transition into his or her responsibilities as the Company's CEO
               (a "Natural Transition"). Employee's responsibilities in any
               Natural Transition would include (i) assisting in the
               identification, selection, and recruitment of a successor CEO,
               (ii) working with the Board of Directors and successor CEO to
               design and implement a transition process that is optimal for the
               Company, and (iii) during such period

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               of up to twelve (12) months after termination of employment as
               may be mutually agreed by the Company and Employee (the
               "Transition Period") making himself available on a mutually
               acceptable schedule for, and providing, such assistance and
               guidance, strategic and otherwise, as the Company or the
               successor CEO may request (but not to exceed 25% of his working
               time during such period, considered in the aggregate and
               exclusive of Employee's duties and responsibilities as Chairman)
               in such areas as operations, marketing, competition, sales,
               investor relations, and the like. Notwithstanding anything to the
               contrary suggested by the preceding sentences of this Section
               7.4, neither Employee nor Company shall have any obligation to
               engage in a Natural Transition."

          1.3  Constructive Termination. Section 7.3(c) of the Original
               ------------------------
Agreement is hereby amended in full to read as follows:

               "(c) a Sale of the Company if Employee is not the Chief Executive
               Officer of the resulting combined entity."

     2.   Stock Option Grant.
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               (a) Option Grant. Effective this 12th day of November 2001,
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Executive shall be granted an option to purchase One Million Three Hundred
Thousand (1,300,000) shares of Common Stock (the "Shares") under the Company's
1999 Equity Incentive Plan. The option shall have an exercise price equal to the
fair market value of Keynote's Common Stock on this day.

               (b) Exercisability; Vesting. The option shall be immediately
                   -----------------------
exercisable subject to a repurchase option in favor of the Company to repurchase
unvested Shares at cost upon termination of employment. The option shall vest
with respect to Twenty Thousand Eight Hundred Thirty-Three and one-third
(20,833) shares on January 7, 2002, with respect to an additional Thirty-Three
Thousand Three Hundred Thirty-Three and one-third (33,333) shares on the 7th day
of each of the twenty-four months from February 2002 through January 2004, and
thereafter with respect to an additional Twenty Thousand Eight Hundred
Thirty-Three and one-third (20,833) shares on the 7th day of each subsequent
month.

               (c) Termination of Option. The option may be exercised by
                   ---------------------
Executive at any time prior to two years after the later to occur of (i)
Executive ceasing to provide services as an employee of the Company, and (ii)
Executive ceasing to provide services as a director of the Company.

               (d) Acceleration of Vesting upon a Sale of the Company. In the
                   --------------------------------------------------
event of a Sale of the Company during the Term, vesting of all then unvested
shares subject to the option shall be accelerated ninety (90) days following
consummation of the Sale of the Company if Executive is not the Chief Executive
Officer of the resulting combined entity, provided however that Executive will
agree not to terminate employment in a Voluntary Termination or Constructive
Termination within a twelve (12) month period following consummation of the

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Sale of the Company, during which Executive may be required to provide
management and transition services for the benefit of the successor entity.

               (e) Effect of Termination Upon Stock Rights. Section 8.5 of the
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Original Agreement is hereby amended in full to read as follows:

                   "8.5 Effect of Termination Upon Stock Rights. In the event of
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any termination of Employee's employment, Employee and Company shall, in
addition to those rights and obligations set forth in paragraph 2(d) of the
Amendment Agreement, have the following rights and obligations with respect to
the Shares:

                   (a) In the event of any termination of employment pursuant
                   to Section 7.1(a), 7.1(b), or Section 7.1(f) (if not in
                   connection with a Natural Transition), vesting of the Shares
                   shall cease on the date of termination of employment and the
                   Company shall have a Right of Repurchase with respect to all
                   of the Shares that are Unvested Shares;

                   (b) In the event of any termination of employment pursuant to
                   Section 7.1(c), (d), or (e) that is not a Natural Transition,
                   an additional number of Unvested Shares shall thereupon
                   become Vested Shares, such number being equal to the number
                   of shares scheduled to become Vested Shares during the six
                   (6) months following termination of employment; and

                   (c) In the event of a Voluntary Termination or Termination
                   Without Cause that is a Natural Transition, vesting shall
                   continue for an additional twelve (12) months."

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     IN WITNESS WHEREOF, the parties hereto have caused this Amendment Agreement
to be executed as of the day and year first above written.

KEYNOTE SYSTEMS, INC.                       EXECUTIVE

By: /s/ John Flavio                          /s/ Umang Gupta
   ----------------------------------       ------------------------------------
   John Flavio, Senior Vice President       Umang Gupta
   Chief Financial Officer

Exhibit A: Stock Option Agreement

                 [Signature Page to Keynote Amendment Agreement]