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Email sizes are fundamental for a few important reasons. One is security, and another is the performance of your email.
Email sizes are fundamental for a few important reasons. One is security, and another is the performance of your email. This article covers, in brief, all you need to know when it comes to email sizes, focusing mostly on email file size limits.
There are three main reasons that there is a max email size set. And they are;
Your and the recipient's email capacity limits the maximum email size. When sending transactional or marketing emails to a large database of email addresses, you should avoid sending messages larger than 10 MB.
Evading spam filters and addressing the recipient's primary folder is difficult in an email. There are no universal malware detection criteria. A round of dup "anti-spam" guidelines includes the size-related criteria.
The SMTP protocol has no text body restriction. Others have their own limitations.
Many operators' tests show a link between email size and deliverability. Messages of 100–150 KB body size usually trigger spam filters. So, maintain email body size between 15 KB and 100 KB.
Large emails also have loading and rendering times. Your recipients don't always have high-speed Internet connectivity; thus, a lengthy email loading procedure may irritate them. Also, huge email bodies may be partially rendered in many email clients, resulting in partial pictures or content clipping. This may negatively impact your customer's digital experience.
Despite the many limits and concealed restrictions, there are basic criteria for creating effective emails. First, reduce and optimize email body size.
Here are the most typical SMTP mail size faults. There are two:
Error code | Description | Reason and how to solve |
---|---|---|
Error 523 | The Recipient's mailbox cannot receive messages this big. | Your message exceeds the size limit of your recipient's server. Check the size of the email body and attachments. Use the recommendations above to optimize it. |
Error 552 | Requested mail action aborted: exceeded storage allocation or size of the incoming message exceeds the incoming size limit. | The email box of your recipient is full. In this case, you have nothing to do: your recipient should clean up his or her inbox. Or your message exceeds the limit set by the administrator. Check the size of your message and optimize it. |
Considering the above constraints, we've devised a quick email size optimization checklist. Here are the guiding principles for creating a list of max email sizes:
Now that you know the fundamentals of max email sizes, you now understand why some emails might not go. You are also better positioned to know how many MB you can send via email and why there is that limit.
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