As a Digital Marketer What Cookies Should You Trust in 2026: A Comparative Study of Client Side and Server Side Cookies.
In our previous blog, we explained what cookies are and what their varieties are. We briefly discussed client side and server side cookies. For digital marketers knowing the features of these two formats of cookies is of utmost importance, a brief discussion is not sufficient, hence this dedicated blog. We are going to talk about how these cookies work, and their features. The purpose of this article is to help you decide which cookies fit which occasions.
Why Do Cookies Exist?
This is just a formality, articles that begin with the basics are the most effective. And here at Gyaner, we believe in effective and simplified teaching. Cookies are simple texts that help sites identify your computer as an individual visitor, it uses this information to personalise your user experience and gain valuable insight about what your preferences are and what you are looking for.
Who Sets These Cookies and How?
Allow me to clear a confusion that you may have. It is not true that all cookies are set by the server as some people seem to think on the internet.
Server Side Cookies are sent to the browser by the server. It is located in the HTTP response header and looks like this : Set-Cookie: token=abc123; HttpOnly; Secure. Notice how the browser has been given a token number (abc123), yes, that helps the server identify individual users.
Client Side Cookies are created by JavaScript. Which your browser runs. How does this happen? The server sends the JavaScript file to your browser along with stuff like HTML, CSS and so on and your browser runs the codes to render the website. While running the Java script, your browser may come across a command which looks like this :
Cookies.set(‘theme’, ‘dark’);.
In human language, this command reads “set a cookie named “theme”, give it the value “dark” and store it in the browser’s cookie storage.” Now you know how a site remembers what theme you used on it last, amongst many other things.
When to use Server Side Cookies?
Server side cookies, only if they have the flag HttpOnly cannot be read by the Javascript. Therefore these cookies are not susceptible to being stolen by parties trying to impersonate you on the internet. First party server side cookies are not restricted by browsers like Safari.
Use them when:
- User authentication is a must
- Sensitive data is involved
- Payment information is likely to be exchanged
- A secure untampered tracking is desirable.
When to use Client Side Cookies?
Client side cookies, as mentioned earlier are created by the JavaScript and are often vulnerable to XSS (Cross Site Scripting) and CSRF (Cross Site Request Forgery), in simpler terms your cookie may be stolen by a third party who wishes to impersonate you on the web. Decidedly, this is a less secure format, but they also have certain upsides and may be considered when:
- Greater user interaction is required like flexibility of language, theme, layout.
- When sensitive information is not being exchanged.
- Session information is to be stored only temporarily and not long term.
A Digital Marketer Walked Into A Bakery, Which Cookie Did They Buy?
A Digital Marketer should try to use Server Side Cookies (HTTP only) whenever possible, because other forms of cookies are being gradually phased out for encroaching upon user privacy. Client side cookies may help you in retargeting campaigns using Facebook pixel, Google ads remarketing tags and so on but ads are increasingly being blocked and you may never reach your audience.
Server side cookies also mostly use first party data, that is data collected directly from the users. Which is naturally more reliable and gives you a more accurate picture of your site’s performance.
To summarise, Server side cookies:
- Survives ad blockers
- Are persistent and last cross session.
- Are SEO friendly, because no JavaScript is involved.
- Conducts authentic tracking, it cannot be manipulated by anyone (ofcourse if the cookies areHTTP only)
- Collects data directly from the users, no foul play involved.
- Provides more accurate results
- Respects the privacy of the users.
Comparisons at a Glance
Feature | Client-Side | Server-Side |
Security | Low – vulnerable to attacks | High – protected from JavaScript |
Setup Difficulty | Easy – just JavaScript | Complex – needs server code |
Performance | Fast – instant access | Slower – server round-trip |
Best For | Preferences, UI settings | Login tokens, sensitive data |
Cost | Low – browser does work | Higher – server processing |
User Control | High – easy to delete/block | Lower – server managed |
Privacy Compliance | Harder to manage | Easier to control |
Conclusion
The future of tracking belongs to server side cookies. As a digital marketer you must keep yourself updated on how each browser treats specific types of cookies. Look up Safari, Chrome, Microsoft Edge and other major browser’s policy on cookies to best take a decision about your campaign. This blog sought to inform you how the two types of cookies function and how they compare with each other. I hope it has achieved its objective but, time passes and the information here may not be true tomorrow, or even an hour later. A digital marketer’s primary tool is research and being up to date. Confused where to start your digital marketing journey? Head over to our official website, Gyaner.com and you shall find that we offer courses. Not only that, you will gain hands-on experience and placement assistance from our amazing faculty, who are also remarkably fun to learn from. Hey, that’s how I got here!
FAQs
Client side cookies are created by your browser’s JavaScript as opposed to being set by the server.
Server side cookies are sent to your browser directly from the server of the website you are visiting, which your browser downloads.
Client side cookies can be stolen by evil parties who wish to impersonate you on the web. Therefore, they are not the safest for the users
Cookies are very necessary for the users to be able to enjoy all the features of a site. Now there are strictly necessary cookies and other kinds of cookies that help optimise user experience. It is now a code to ask the users if they want the cookies which are not strictly necessary. If any cookie is being planted without the user’s knowledge that is unethical.
You must use server side cookies when your site involves the exchange of personal information and money transfers. Apart from this, server side cookies (HTTP only) are more reliable collectors of information since they are not usually blocked by browsers and they collect data directly from the users.
Client side cookies should be used with caution. Use it only when no sensitive information is being exchanged. They are susceptible to cross site scripting (XSS) and cross site request forgery (CSRF)