What is Performance Testing? Difference Between Performance Testing, Load Testing and Stress Testing – With Examples

Hi Readers! In the testing world, many times we come across the terms like performance testing, load testing, and stress testing. These three terms are often misunderstood and interpreted as same concepts. However, there is a significant difference between these three testing types and it is important for a tester to understand the same.

In this article, we will discuss each of these 3 testing types to understand the difference between them.

Q. What is the difference between Performance Testing, Load Testing, and Stress Testing?

What is Performance Testing_ Difference Between Performance Testing, Load Testing and Stress Testing – With Examples

#1) Performance Testing:

=> Click on below link to know more about PT:
What is performance testing?

Performance testing is the testing which is performed to ascertain how the components of a system are performing under a particular given situation. Resource usage, scalability, and reliability of the product are also validated under this testing. This testing is the subset of performance engineering, which is focused on addressing performance issues in the design and architecture of software product.

Performance Testing

The above image tells us clearly that performance testing is the superset for both load & stress testing. Other types of testing included in performance testing are spike testing, volume testing, endurance testing and scalability testing. So, performance testing is basically a very wide term.

Performance Testing Goal:

The primary goal of performance testing includes establishing the benchmark behaviour of the system. There are a number of industry-defined benchmarks which should be met during performance testing.

Performance testing does not aim to find defects in the application. It also does not pass or fail the test. Rather, it addresses the critical task of setting the benchmark and standard for the application. Performance testing should be done very accurately. Close monitoring of the application/system performance is the primary characteristic of performance testing.

The benchmark and standard of the application should be set in terms of attributes like speed, response time, throughput, resource usage, and stability. All these attributes are tested in a performance test.


For instance, you can test the application network performance through ‘Connection Speed vs. Latency’ chart. Latency is the time difference between the data to reach from source to destination. A 70kb page would take not more than 15 seconds to load for the worst connection of 28.8kbps modem (latency=1000 milliseconds), while the page of the same size would appear within 5 seconds for the average connection of 256kbps DSL (latency=100 milliseconds). And, a 1.5mbps T1 connection (latency=50 milliseconds) would have the performance benchmark set as 1 second to achieve this target.

Another example would be of Request-response model. We can set a benchmark that the time difference between the generation of request and acknowledgement of response should be in the range of x ms (milliseconds) and y ms, where x and y are standard digits.

Performance Load and stress testing

A successful performance test should project most of the performance issues, which could be related to database, network, software, hardware, etc.

#2) Load Testing:

Load testing is meant to test the system through constantly and steadily increasing the load on the system until it reaches the threshold limit. It is a subset of performance testing.

load testing

Load testing can be easily done by employing any of the suitable automation tools available in the market. WAPT and LoadRunner are two such famous tools that aid in load testing. Load testing is also famous by the names like volume testing and endurance testing. However, volume testing mainly focuses on databases. And endurance testing tests the system by keeping it under a significant load for a sustained time period.

The sole purpose of load testing is to assign the system the largest job it can possibly handle to test the endurance of system and monitor the results. An interesting fact here is that sometimes the system is fed with the empty task to determine the behaviour of the system in the zero-load situation!

The attributes which are monitored in a load test are peak performance, server throughput, response time under various load levels (below the threshold of break), adequacy of H/W environment, how many user applications can handle without affecting the performance.

Load Testing Goal:

The goals of load testing include:

  • Exposing the defects in application related to buffer overflow, memory leaks and mismanagement of memory. The issues that would eventually come out as the result of load testing may include load balancing problems, bandwidth issues, the capacity of the existing system, etc.
  • To determines the upper limit of all the components of application like a database, hardware, network, etc. so that the application can manage the anticipated load in future.
  • To set the SLAs for the application.


For example, to check the email functionality of an application, it could be flooded with 1000 users at a time. Now, 1000 users can fire the email transactions (read, send, delete, forward, reply) in many different ways. If we take one transaction per user per hour, then it would be 1000 transactions per hour. By simulating 10 transactions/user, we could load test the email server by occupying it with 10000 transactions/hour.

Another example of load test is shown in the image below:


The above image depicts a load test done in the tool called JMeter. This test is done to identify that how many users a system can handle. In this test, 100 users are added after every 30 seconds until the load reaches 1000 users. Each step takes 30 seconds to complete and JMeter waits for 30 seconds before kicking off the next step. Once, the load reaches 1000 threads, all of them will continue running for 300 seconds (5 mins) together and then finally stop 10 threads every 3 seconds.

#3) Stress testing

Under stress testing, various activities to overload the existing resources with excess jobs are carried out in an attempt to break the system down. Negative testing, which includes removal of the components from the system is also done as a part of stress testing. Also known as fatigue testing, this testing should capture the stability of the application by testing it beyond its bandwidth capacity.

So, basically, stress testing evaluates the behaviour of the application beyond peak load and normal conditions.

Stress testing

The purpose of stress testing is to ascertain the failure of the system and to monitor how the system recovers back gracefully. The challenge here is to set up a controlled environment before launching the test so that you can precisely capture the behaviour of system repeatedly under the most unpredictable scenarios.

The issues that would eventually come out as the result of stress testing may include synchronization issues, memory leaks, race conditions, etc.

If the stress test is checking that how the system behaves in the situation of sudden ramp up in the number of users, it is called a spike test.

If the stress test is check system’s sustainability over a period of time through slow ramp up in the number of users, it is called as a soak test.

Stress Testing Goal:

The goal of the stress testing is to analyze post-crash reports to define the behaviour of the application after failure. The biggest challenge is to ensure that the system does not compromise the security of sensitive data after the failure. In a successful stress testing, the system will come back to normality along with all its components even after the most terrible breakdown.


As an example, a word processor like Writer1.1.0 by OpenOffice.org is utilized in the development of letters, presentations, spreadsheets etc.  The purpose of our stress testing is to load it with the excess of characters.

To do this, we will repeatedly paste a line of data, till it reaches its threshold limit of handling a large volume of text. As soon as the character size reaches 65,535 characters, it would simply refuse to accept more data. The result of stress testing on Writer 1.1.0 produces the result that it does not crash under the stress and it handles the situation gracefully which makes sure that application is working correctly even under rigorous stress conditions.

Another example of load test is shown in below image which depicts a spike test through sudden ramp-up of 7000 users:

Stress Testing Goal example


To summarize, I would quickly put the major differences between these 3 testing types in the table below:

 Performance TestingLoad testingStress testing
DomainSuperset of load and stress testingA subset of performance testing.A subset of performance testing.
ScopeVery wide scope. Includes - Load Testing, Stress Testing, capacity testing, volume testing, endurance testing, spike testing, scalability testing and reliability testing, etc.Narrower scope as compared to performance testing. Includes volume testing and endurance testing.Narrower scope as compared to performance testing. Includes soak testing and spike testing.
Major goalTo set the benchmark and standards for the application.To identify the upper limit of the system, set SLA of the app and see how the system handles heavy load volumes.To identify how the system behaves under intense loads and how it recovers from failure. Basically, to prepare your app for the unexpected traffic spike.
Load LimitBoth – below and above the threshold of a break.Till the threshold of breakAbove the threshold of break
Attributes studiedResource usage, reliability, scalability, resource usage, response time, throughput, speed, etc.peak performance, server throughput, response time under various load levels (below the threshold of break), adequacy of H/W environment, the number of user app can handle, load balancing requirements, etc.Stability beyond bandwidth capacity, response time (above the threshold of break), etc.
Issues identified through this testing typeAll performance bugs including runtime bloat, the scope for optimization, issues related to speed, latency, throughput, etc. Basically – anything related to performance!Load balancing problems, bandwidth issues, system capacity issues, poor response time, throughput issues, etc.Security loopholes with overload, data corruption issues at overload situation, slowness, memory leaks, etc.


We have seen and understood through discussion and examples that how performance testing, load testing & stress testing are different from each other and what is the scope of each testing type.

We are sure that this was helpful for you to understand and differentiate practically between these three concepts.

Further reading

Have queries on Software Testing? All you need to do is post your questions in the comment section below.


#1 Vamsi Krishna

these are confusing terminologies especially when asked in interviews :) thanks for clearing the doubts.

All these testing types are very important for application stability and scalability. In agile testing environment most testers fails to perform performance testing, rather projects from the service industry don’t give much importance for performance.

The best and easiest to learn website load testing tool I found and used is JMeter.

#2 Nirav

Excellent. Thanks

#3 Gaurav Khanna

It is very clear and easy to understand. Thanks you for posting such a nice blog.

#4 Pooja

Very informative and well explained.
well said by Vamsi these terms are always told to be like similar one but here lies the difference explained by you

#5 Ravi

Nice article…

#6 Jagdish

Can you tell me that how to perform Stress, Load and performance testing. How we test admin?

#7 Srivalli

Similarly can you explain below questions with simple explanation from interview point:

1. What is difference between Manual Testing and Automation Testing?
2. What is difference between Testing and QA?
3. How to approach for a QA/testing job?




Good work, these topics are always confuse us. But now it is clear. Please give brief on Unit, Integration, System, Acceptance and Regression testing. If anyone can do this I will thankful for that.

#10 Raju Phatak

Very good artical on PSR testing. Its explained with exapmple in a simple language. Kindly post some more articals on this.

#11 Reddy Siva Saran

Nice article and good explanation

#12 pravin

hi….nice article

#13 Yamraaj

Very nice article, simple explanation with easy to understand examples. Very good help for all especially for the beginners.

#14 Rajendra

Excellent Article..!!!!

#15 Jitendra Bhande

best Article …..

#16 Deepak yadav


#17 sweta dubey

very good example.provide few more for better understanding and ease.

#18 karamjeet

nce gidence and good explan for software testing…….

#19 Pratap

Hi all

Can anybody tell me how to test a website in which

“iFrames” plays a very important role.

i mean few things that i must remember while testing

these kind of site ?

plz help me guys

#20 Tal

people always confuse load and stress testing. sometimes the tests could be very similar, but like you said, the goal is different…

#21 Jagadish


Presently i ma working in non-it industry, having an experience of 5+ years in the non-it field.i am thinking shift into the software testing field.

Please guide me how can i proceed.

With regards



#22 vikas

hi all!
i am searching for interview questions that are been asked to experienced candidates.i mean those who alredy have experience of 1 yr-2 yrs.
wil b thankful.

#23 sandeep redhu

thaxxxxx….its really help for us…

#24 gan

my doubt is ….. in companies separate roles will be there?
i mean performance tester?
load tester?
stress tester?
else all three are same..i have little bit confusion …. clarify anybody pls

#25 Animesh

they are really usefull

#26 Animesh


#27 Swati Namdeo

Please give me answers to these questions..
1) difference between retesting and regression testing with example?
2) what is STLC ?
3) when smoke & sanity testing is performed? please explain these with example.



#29 Lizzi


#30 kulbir


#31 geeta

Nice explanation and good to understand

#32 Anand Kulkarni

Very crisp, up to the point explanation.
It helps me learning Performance Testing.

#33 Hitesh

Elegant description about testing

#34 shalini dinavahi

hi friends..
i am a telecom testing proffesional,i would like to make my career in TESTING in IT domain,kindly help me how can i proceed further

Thank you
Shalini dinavahi

#35 Vishal

Thank….it really helped me to clear the difference between the two…..

#36 Trivikram

Thanks for a very informative article.

#37 Charu

How can we do performance, stress and load testing without automation tool ?

#38 agile load testing

Thanks for this bright explaination

#39 kumesh

good deffination

#40 Supriya

my doubt is ….. in companies separate roles will be there?
i mean performance tester?
load tester?
stress tester?
else all three are same..i have little bit confusion …. clarify anybody pls

#41 Ravi

Hi.. nice article..
I have a different view on the volume testing and endurance testing.
Volume testing is done with huge volume of data in the database keeping in mind, future growth in the data. Ideally we insert huge data in the database and do the testing. And Endurance testing is to test application stability for the extended time or duration. the main idea of endurance testing is to check for the memory leakage in the application. Ex: GC is happening properly without any issues..
Correct me if i m wrong.
Cheers :)

#42 Anshu

Great article but I agree to what Ravi said. Endurance testing is different from any amongst Performance, Load or Stress. Although I am still apprehensive by the definition of Volume testing given so far. Expert opinions welcomed!

#43 kaushaya

hi, i have one year experience in manual testing and that too i have tested “education system software” i want to switch to finance and banking domain,from i can get knowledge in this domain so that i can clear interviews please help me

#44 Abdul Ghaffar

Excellent differeciation bw the terms……….

#45 radheshyam

descriptin excelent,good contents,

#46 parag patil

Thanks for the Post
all the things are very nicely explained .

#47 Nimesha

It’s really clear and understanderble.. Thanks a lot for this clear explanation :-D

#48 Amit Kumar Thakur

I like this.

#49 Musab Rasheed

Thank you for every thing, specially for examples.

#50 chetan

How to test the database stress testing (i.e. how to test affect of heavy data on application). any idea or tool please share.

Thanks in advance,

#51 Frank

Wonderfully explained in a very comprehensive way. Thank you.

#52 Makesh

Nice and clear :)

#53 Rina

hi, pls tell me Manual Testing logical question answer & ISTQB exam paper.

#54 satish Namburi

Hi Every one,

Am New to Performance Testing,
Am Working with VS2012 Ultimate Version.

I Have some doubts regarding,
What is Scalability?
What is Stability?
What is Stress Test?

and What are the major differences between these tests.

How to perform these tests on web appplication?

Looking for a better solutions..

Thanks in advance:)

#55 madhavilatha

Hi Every one,

any one can you please give me performance(load,stress,scalability,stress) test cases for windows application?

#56 supriya


#57 dian

can i have information about tools for performance testing when an application are access by so many users?
tell me, please. thank you

#58 Pavan

Nice article even for an experienced tester or a beginner

#59 Dhanish


#60 peter


#61 Satham

It is very useful to me , thank you…..

#62 Pierre

Hi Vijay,

Great article – thanks.
Who in your opinion are the 3 most respected independent 3rd party testing companies for perfomance, load and stress testing.


#63 Mohit

Very nicely and clearly described. Well orientation as these are the mostly asked questions, confusing and similar terms.
Examples are too self explanatory.


#64 krish

Hi sir,

you are articles are very nice and helpful for freshers and experience persons. i am from non it background i wnat to do performance testing.Can any one please reply me what are the skills reqired for a performance tester.

#65 Goutham

good article really very helpfull thanku so much

#66 Hai Le

I was very confused of those terms. Thank you for the very helpful article.

#67 Hamza Hashmi

Love that. Thank You :)

#68 Anamika


I faced this interview question yesterday.

Q. How are performance testing and load testing related?

Please explain how can i describe relationship between these two types of testing.



#69 Rakesh

This is a very misleading article. I don’t know where you got this information from.

There is nothing called performance test as such, any test that is executed to validate performance of an application falls under various types of Performance test.

Load , Stress, Endurance and Volume tests are some of the types of Performance testing.

Load test is the simplest type of all the Performance tests. I request all the readers to searc for better resources to learn about Performance testing.

#70 Rakesh

Load test is executed to validate if application is simply meeting the performance goals that were defined, when tested with a defined load, defined hardware and configurations.

Endurance tests are executed to uncover any performance issues that can only happened during prolonged periods of sustained load. One of the main reason to execute Endurance tests are to uncover memory leaks in the application code, which is hard to acheive in short duration tests.

Volume tests are executed in two cases_

1. To validate the application performance behavior with varying amounts of data volumes in the database or
2. To measure the applications ability to process large amounts of data, for example batch processing like generating payrolls in PDF format or importing large volumes of data from a File into database, etc

Stress tests are executed to identify the application behaviour when the application is subjected to a far greater load than it is expected to handle or designed to handle. Stress test usually is executed with more concurrent users than the target load and/or by sending more number of requests than the original target.

So, the branch of QA or Engineering which deals with identifying load characters, planning, identifying the required tests, creating scripts, executing tests, analyzing the results, preparing reports and providing the summary of performance issues, is called Performance testing. Performance test is not a test type, it is a generic name for any of the types of tests that are exeucted to validate performance and identify performance issues…

There are many good books, ebooks which provides you proper understanding of the Software Performance concepts. Always, go through the author credentials before reading their content.

#71 Rob

Comments are even more valueable resources!

#72 Saikiran

What is the difference between aging testing and stress testing?

#73 Carrie

Apica is a great site that helps with load testing, and they have a 30-day free trial, with no credit card information required.

#74 Mukesh


I have little bit confuse between Load, Stress and Performance. Please can you explain about clearly.

#75 Mark

I’ve never seen an article with so much nonsense in it.
Readers, please, please, please go elsewhere for your knowledge of performance testing

#76 Rizwan

Nice Article

#77 saravana kumar m

apply the functional testing concepts for the real time examples
apply the non functional testing concepts for the real time

#78 Sai Shinde

Hi All I have been attending performance testing interviews since last 3 months to collect all real time performance testing interview questions.If any one needs plz reach out at saishi219414@gmail.com.


#79 arun mohanty

What is performance testing?
As you have written”This testing is the subset of performance engineering”.
Pls correct me if i am wrong”Performance engineering starts with performance testing and it ends with performance testing then performance engineering is asubset of performance testing but not “This testing is the subset of performance engineering”.”

#80 pooja

very informative……..thanks a lot..so nicely explained

#81 Nayan Chauhan

nice blog post. nicely describe to performance testing and load testing useful for me.complete guidance mentioned in it. thank you for sharing with us.

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