What Does A Spam Filter Look For?
You need a spam filter to “filter any unwanted or suspected spam!” Spam is annoying and time-consuming to get rid of manually, and may contain viruses and spyware that can damage one’s computer. The spam filter is therefore installed so that it may stop or block any suspected spam.
If you send an email, it will pass through filters that will either deliver it to the inbox, a categories tab, or a spam folder, or it will be blocked completely. For you to confidently answer the question, “What do spam filters look for?” you have to know, “What is a spam filter, and how it works?”
The spam filter is a program that detects unsolicited, unwanted, malicious, and virus-infested email (spam) and blocks it from getting into the email inboxes. Spam is a major problem on today’s internet and it brings financial damage to companies and annoys individual users. Thus, a spam filter plays a big role in the success of email campaigns. It scans through a message and looks for certain criteria on which it bases judgments on whether it’s spam or not.
What does a spam filter look for?
Installed spam filters might look for the following in an email message:
- Spammy topics
- Grammar and spelling
- Language and character set; for example a foreign to both the sender and the receiver.
- Just a link only in an email message.
- HTML mail: simply sending a message in this format is a sign of possible spam.
- Email messages with images are also common in spam.
- Spacing in the message body.
- Unseen headers in the message.
These are among many other criteria that a spam filter may look for in a message.
The most effective spam filter techniques
A spam filter is installed on an email server whose main purpose is to analyze incoming and outgoing emails. It uses a set of programmed instructions to decide which ones are spam. They can take on several roles like content filtering, blacklist filtering, malware filtering, and virus detection, among others. There are many different ways to deal with spam, and below are among the most effective ones.
1. Filtering by content
This technique blocks spam by filtering some common words used in spam emails. These words may include “additional income”, “cash bonus”, and some claims “one’s a winner”. You can filter these words or emails containing such topics.
2. Avoiding posting Your Email ID publicly on the internet
You should always avoid posting real email addresses to public lists and forms if it’s not out of necessity. This will ensure that your email is safe from getting into the hands of spammers who may misuse it for their crooked illegal gain. If it’s necessary to post your email to the public, you can use extra spaces or preferably replace the ‘@’ symbol with ‘at’. This reduces the chance of spambots finding your real email ID online.
3. Use an Effective Anti-spam Solution
Anti-spam offers spam filtering solutions that are effective in dealing with spam as they will prevent spam emails even before they reach your inbox. Apart from automatically quarantining the spam emails, they have other many benefits like you will have a limited number of false positives, and filtering 99.9% of spam from reaching the inbox.
How to Customize Gmail Spam Filtering.

Features of relevant spam filter services
According to security experts, the best spam filter service is one that’s compiled multiple features to protect businesses from excessive levels of spam emails and the threats that accompany them, for example, malware, phishing, ransomware, etc. However, deciding which features should be the priority when choosing the best spam filtering services for business might be slightly confusing. Below are common-relevant features of spam filtering services:
- Ease of operation: the best filtering service should not be too complicated to operate otherwise it will be of no value. Therefore, whatever solution you choose to protect businesses from spam must be user-friendly.
- Greylisting: this can prevent the delivery of emails from previously unknown sources instead of from known sources. To achieve this, it returns non-whitelisted emails to their originating servers with a request for the email to be resent. Since spammers’ servers are mostly too engaged to respond to the request, the spam email never comes back.
- Accelerated filtering rates: With fewer emails going beyond the Greylisting process, the remaining emails are filtered at an accelerated rate. This can be used to a business’s advantage to reduce the administrative burden, and better protect against email-borne threats, as it won’t be so necessary to whitelist so many “trusted” senders in order to avoid delays in the delivery of their emails.
Other features:
- Outbound email scanning: this is a valuable security tool for identifying business email accounts (which are trusted by the receiver) that have been compromised and are being used by attackers to distribute spam or malware. This protects your business’s reputation with other partners, other important entities, and also other internal threats.
- Advanced Anti-virus software: they mostly work by scanning devices and networks for the presence of malware after it is deployed. The best spam filter service will scan both inbound and outbound emails and their attachments for malware as they flow through the mail server in order to identify threats before they have the opportunity to be deployed.
Also, Check This Ultimate Guide For The Effective Spam Filtering Solutions.
Manually deleting spam messages is time-consuming and installing a spam filter can also be expensive. However, a variety of free spam blockers and free spam filters (for example spam filter Gmail) are available and you can employ the use of the best free spam filter to stop spam messages from landing in one’s inboxes.
Final words on the spam filter
Finally, a spam filter looks for certain “spammy criteria” in one’s messages. Each criterion gets a different score and the total score determines whether the message is blocked as spam or not. Thus, sophisticated email filtering systems can use a specific email message to analyze it to see what characters it has, and update the things that spam filter looks at to check for spam for everyone.