SEO vs SEM: What's the Difference

Staff Writer
Last Updated
February 9, 2024
Table of Contents
tocitem toc-h2
tocitem toc-h3

Many technical terms are circulating in the world of digital marketing, but none are as popular as Search Engine Optimization (SEO) and Search Engine Marketing (SEM). While both aim to increase a website’s visibility and rankings on search engines, each one achieves this in entirely different ways with distinct techniques and strategies. SEO focuses on optimizing a website’s organic visibility in search engines, while SEM uses paid advertising to achieve this.

Here’s a table summarizing the differences between the two:

Methods Improving website traffic and engagement through website optimizations, content production, and link building. Improves website traffic and engagement by creating advertisement campaigns and bidding on specific keywords.
Cost Costs involved with the hiring of SEO agencies and professionals to execute SEO strategies for your website. Operates on a cost-per-click model where specialists pay search engines for every user click.
Results and Visibility SEO is a long-term strategy that may take a while to yield results. It aims to boost a website’s rankings on search engines and requires constant maintenance. After successfully acquiring a keyword, there will be immediate results as the paid advertisement will appear as the first item when the keyword is searched.
Control SEO has relatively less control as the success of a campaign is ultimately up to the search engine algorithms. SEM specialists have control over ad placements, audience targeting, budget allocations, and launch dates.

What is SEO?

As mentioned before, both SEO and SEM aim to improve a website’s online engagement by improving its ranking on search engine results pages, but SEO does this by focusing on organic and unpaid traffic, as well as bettering a website’s content and structure to align with what search engines are looking for in a high-quality website.

This makes SEO a much more long-term strategy with a sustainable progression and improvement compared to SEM. While SEO focuses on optimizing a website’s organic visibility in search engines, SEM uses paid advertising to achieve this.

How Does SEO Work?

SEO specialists and teams continuously work to better the quality of both your website and its content to make it more appealing to search engine algorithms, and they do this by using some common methods and practices.

Keyword Optimization

This process is all about finding and choosing the right keywords that align with your business activities and goals, and it’s always the first step to every successful SEO strategy. By finding out what people are searching for online, as well as what their search intent is, you’ll be able to curate high-quality content that gives them exactly the information they’re looking for, which can help attract more traffic and readers to your site.

On-Page Optimization

Search engines get a good idea of what a certain page on your website is all about by looking at a few things like titles, headers, meta descriptions, links, and the body of the content. By strategically including in-demand keywords and queries in these areas, you’ll have a much better chance of being seen favorably by the search engine algorithms, which can help you land a much better landing on the results pages.

Quality Content

Even with all the optimizations implemented on your website, it’s still very important to produce and publish great content that appeals to your readers and target audiences. When creating content, make sure that it's informative, original, and engaging. It also helps to write with a more casual tone that aligns with everyday speech.

Readers will respond much more positively to this as opposed to poorly written content that can negatively affect your online performance and lead to an increase in bounce rates—the amount of visitors that leave your website without interacting with it.

Link Building

Link building is the process of acquiring high-quality backlinks from other reputable websites that lead back to your website. In the world of SEO, these links are seen as endorsements by search engines that your website is credible and trustworthy, which can help work in your favor when you’re looking to increase your organic traffic.

Technical SEO

Another important factor that influences your performance on search engine results pages is the technical elements of your website. This includes things like your website’s structure and loading speed, as well as whether it’s optimized for mobile devices. It’s also crucial to ensure that your website can be properly indexed and crawled by search engines.

Technical SEO optimizations also inadvertently improve user experience by providing a more seamless and smooth experience for them.

What is SEM?

While SEO improves brand visibility by boosting organic traffic, SEM does this through paid advertisements and campaigns that appear on popular search engines for users to see. This is done most commonly with the help of Google Ads, and Bing Ads, as well as on different social media platforms such as Facebook and Instagram.

How Does SEM Work?

Similar to SEO specialists, SEM specialists and professionals are responsible for the planning, execution, and management of a brand’s paid advertising campaign. There are a few things that SEM specialists pay close attention to, and these are some of the key aspects.

Keyword Research

SEM also involves keyword research, which allows specialists to find what customers are searching for. This is especially important in SEM as you’re going to want your ads and campaigns to show up on search results that are relevant to your message. However, unlike in SEO, keyword research in SEM also serves the purpose of getting an estimate of how much ads are likely to cost, and this varies depending on the keyword.


Once you’ve decided which keywords you’d like to target, it’s time to send a bid, which basically tells Google how much you’re willing to pay for each ad click. This will be done in competition with other specialists. If someone else has sent a higher bid and has equally or more relevant ads than yours, then it’s likely that Google won’t feature your ad as much, which can lead to a smaller amount of clicks.

Paid Ad Quality

This is where Google’s Quality Score will come in especially handy as it’s a great metric to gauge how good of a match your ad is to the user’s search queries. The Quality Score of your ad is calculated based on the click-through rate, the quality of the landing page, and the overall Quality Score of the Google account being used.

Naturally, ads with higher Quality Scores will be seen by a wider audience, and it’ll also give you a discount on how much you have to pay for each click.

Audience Targeting

This involves deciding the message that you want your ad to communicate, as well as the link that it will send people to. With SEM, you’ll be able to reach users based on their demographics, locations, devices, search history, and interests.

SEO vs SEM: What's the Difference?

Now that we have a general understanding of the two, it’s time to break down their main differences in terms of cost, speed of results, and the amount of control you have over the outcome.


SEM: SEM works on a cost-per-click model where specialists and advertisers pay search engines like Google every time that a user clicks on their ads. This can be slightly discounted for ads that get a high Quality Score, but it’s also worth considering the cost of creating high-quality and effective ads.

SEO: Many people think that SEO is unpaid as it focuses on organic traffic, but there are costs associated with hiring the right SEO services and professionals to find the right keywords, create high-quality content, and optimize your website for search engines. 

Results and Visibility

SEM: On search engines like Google, ads typically appear as the first item on results pages, and this grants your brand immediate visibility as long as you continue to run paid campaigns and pay Google its share in the profits. Naturally, your ads will no longer be displayed or visible once you stop spending.

SEO: SEO is a long-term strategy that may take some time to yield results. Depending on your website’s ranking at the start of the SEO campaign, it can take some time for your website to gain the amount of visibility and traffic that you want. And even when you achieve a desirable ranking, this will still need to be actively improved and maintained.


SEM: SEM specialists and advertisers have a relatively high degree of control over their ad placements, as well as audience targeting and budget allocations. They can also decide when their ads and campaigns will be launched, consequently deciding when they want to see immediate results.

SEO: Unlike SEM, the effectiveness of SEO strategies and campaigns is ultimately left to search engine algorithms. The best thing that SEO professionals can do is to optimize your website’s structure, keyword usage, and content with the hopes that these will yield a better ranking on search engines.

SEO or SEM: Which One is Better?

Neither one is better than the other because it’s all about what you’re looking for. SEM is great for instant and quick results and a rapid rise in your website’s rankings that are also friendly for your budget. SEO, on the other hand, will deliver much more sustainable and lasting results although it’ll take longer to see any significant changes.

Elevate your online presence with our top SEO Singapore services. At Cardinal Digital, we specialize in optimizing websites for superior rankings and increased visibility. Our expert team tailors strategies to make your brand stand out, ensuring success for startups and established businesses alike. Transform your website into a digital powerhouse by partnering with us. Contact us now for a consultation and take the reins of your online success.

No items found.
Get in touch with us now

We work with an experienced team of marketers and media strategists to help deliver the most optimal results for your business objectives.

Thank you for reaching out! Our team will review your info and reach out if there's a potential fit.
Oops! Something went wrong while submitting the form.