The following are the most commonly asked questions about our Deliverability Tools and other deliverability issues.
As a reminder, check out our Deliverability onboarding video:
Questions about Deliverability Tools
What are the size limits of the emails and what triggers the different warnings in the tools?
The email sizes and the warning thresholds are specified in the following table:
Condition |
Warning level |
email size >= 15KB and email size <= 100KB | OK (green) |
email size > 100KB and email size <= 110KB | Warning (orange) |
email size < 15KB or email size > 110KB | Error (red) |
How much time is needed after campaign launch for Deliverability Report to collect and display any results?
The data is loaded into the Deliverability Report database every 4 hours. However, since deliverability data depends highly on the actual behavior of the contacts, it may make more sense to check the results 12-24 hours after campaign launch. By that time the data should stabilize and will not be prone to change drastically.
For how long are the results of campaigns stored?
Domain-level opens and clicks are calculated from the Emarsys database, using our contact behavior data. This data is usually kept for 13 months.
I can't see my local ISP in the Top 10 list of domains, but I would like to monitor the results of smaller domains, is there a way to do that?
The report database only calculates the results for the Top 10 domains for each launch. If you want to get more granular results you need to split your recipient list with this in mind. This can be done with A/B versions or child campaigns, too.
General questions about deliverability
What is IP reputation?
IP reputation is the ISPs first impression of you, when they determine the Spam Score of your email. This shows the state at the moment of sending and it is one of the most objective metrics to show your general reputation.
What is Spam Score?
ISPs want to filter out spam for your contacts. Spam mail is not only unwanted, but can also contain phishing links, and other malicious things. To this end, they have a scoring system, called Spam Scoring.
The Spam Score is ever changing, and the metric is not public, but when you are sending, ISPs assess every mail based on the sender domain.
First, they check the authentication of the email. If it is OK, they check image and link domains, looking for phishing links. They also check the content against best practices; our Deliverability Advisor is helpful in this field: e.g. is there a text version, are you sending consistent volumes?
If you think that your Spam Scoring may be high, you can use IP warm-up to handle this.
What is IP warm-up?
When you start to use a new IP address, you have to introduce yourself to the ISP. This is called IP warm-up.
Take your whole contact list and segment to your absolutely most engaged contacts, the ones that will most certainly open and click, and start sending good content to these contacts. During the warm-up process, you build your reputation in about four weeks, with consistent volume and consistent content. You can slowly increase the number of contacts you are sending, until you reach the desired size of the segment.
If you miss this, the ISP will only see the highly inconsistent increase in volume and they will most likely handle you accordingly (e.g. block).
IP warm-up can also be used to tackle deliverability problems.
Account management
Can I use the same reply address in multiple accounts?
You can use the same reply address, but since this can affect your deliverability, as best practice, we strongly recommend separating your marketing and transactional sender addresses, based on the actual use case.
Can I send transactional and marketing emails from the same IP?
Yes, but an IP with a low reputation can seriously affect your deliverability. As best practice, separate your marketing and transactional emails. In general, transactional messages have better engagement and thus better deliverability, and if you do not separate marketing from this, your potential marketing problems will affect the inbox placement of your transactional mails, too.
However, maintaining a good deliverability is not rocket science, you just need to be mindful about your strategy and apply best practices.
You can check your reputation at Senderscore.org or in the Deliverability Advisor.
Can my account's blocklist be filled automatically (e.g. as a feed)?
No, unfortunately, this is not possible. However, your account's blocklist can be updated via the API. For more information, see Blocklist Emails and Domains.
Can I update my account's blocklist at any time?
Yes, but please note that no imports are processed between 6-11 AM GMT+1 (Vienna time). This practically means that in the worst case, an update at 6 AM may take 5 hours to process.
By using the API, your account's blocklist is updated in real time.