Website review smtpfieldmanual.com
SMTP Error Codes in the Wild | SMTP Field Manual
Generated on March 31 2026 15:29 PM
Old data? UPDATE !
The score is 64/100
SEO Content
Title
SMTP Error Codes in the Wild | SMTP Field Manual
Length : 48
Perfect, your title contains between 10 and 70 characters.
Description
A collection of raw SMTP error responses from major email service providers and spam filters.
Length : 93
Great, your meta description contains between 70 and 160 characters.
Keywords
Very bad. We haven't found meta keywords on your page. Use this free online meta tags generator to create keywords.
Og Meta Properties
Good, your page take advantage of Og Properties.
| Property | Content |
|---|---|
| title | SMTP Error Codes in the Wild | SMTP Field Manual |
| description | A collection of raw SMTP error responses from major email service providers and spam filters. |
| type | website |
Headings
| H1 | H2 | H3 | H4 | H5 | H6 |
| 1 | 4 | 2 | 0 | 1 | 0 |
- [H1] A collection of raw SMTP error codes spotted in the wild
- [H2] What is this?
- [H2] SMTP Error Codes
- [H2] Email Providers
- [H2] Spam Filters
- [H3] 4.X.X Persistent transient failure
- [H3] 5.X.X permanent error
- [H5]
Images
We found 3 images on this web page.
2 alt attributes are empty or missing. Add alternative text so that search engines can better understand the content of your images.
Text/HTML Ratio
Ratio : 3%
This page's ratio of text to HTML code is below 15 percent, this means that your website probably needs more text content.
Flash
Perfect, no Flash content has been detected on this page.
Iframe
Great, there are no Iframes detected on this page.
SEO Links
URL Rewrite
Good. Your links looks friendly!
Underscores in the URLs
Perfect! No underscores detected in your URLs.
In-page links
We found a total of 50 links including 0 link(s) to files
| Anchor | Type | Juice |
|---|---|---|
| Postmark | External | Passing Juice |
| SMTP Codes | Internal | Passing Juice |
| Email Providers | Internal | Passing Juice |
| Spam Filters | Internal | Passing Juice |
| Contribute | Internal | Passing Juice |
| Why we built this → | Internal | Passing Juice |
| 421 | Internal | Passing Juice |
| 422 | Internal | Passing Juice |
| 450 | Internal | Passing Juice |
| 451 | Internal | Passing Juice |
| 452 | Internal | Passing Juice |
| 501 | Internal | Passing Juice |
| 540 | Internal | Passing Juice |
| 550 | Internal | Passing Juice |
| 551 | Internal | Passing Juice |
| 552 | Internal | Passing Juice |
| 553 | Internal | Passing Juice |
| 554 | Internal | Passing Juice |
| Amazon Simple Email Service | Internal | Passing Juice |
| Apple | Internal | Passing Juice |
| AT&T | Internal | Passing Juice |
| Comcast | Internal | Passing Juice |
| Free | Internal | Passing Juice |
| GMX | Internal | Passing Juice |
| GoDaddy | Internal | Passing Juice |
| Internal | Passing Juice | |
| Hey | Internal | Passing Juice |
| Hostpoint | Internal | Passing Juice |
| ImprovMX | Internal | Passing Juice |
| Infomaniak | Internal | Passing Juice |
| Mail.ru | Internal | Passing Juice |
| Orange | Internal | Passing Juice |
| Outlook | Internal | Passing Juice |
| ProtonMail | Internal | Passing Juice |
| Internal | Passing Juice | |
| Rackspace | Internal | Passing Juice |
| Rambler | Internal | Passing Juice |
| Web.de | Internal | Passing Juice |
| Yahoo Inc | Internal | Passing Juice |
| Yandex | Internal | Passing Juice |
| Zoho | Internal | Passing Juice |
| Barracuda | Internal | Passing Juice |
| Cisco | Internal | Passing Juice |
| Email Security.cloud | Internal | Passing Juice |
| Exchange Online Protection | Internal | Passing Juice |
| FireEye | Internal | Passing Juice |
| Mimecast | Internal | Passing Juice |
| Proofpoint | Internal | Passing Juice |
| Trend Micro | Internal | Passing Juice |
| ZeroSpam | Internal | Passing Juice |
SEO Keywords
Keywords Cloud
smtp manual wild codes postmark field provider couldnt email error
Keywords Consistency
| Keyword | Content | Title | Keywords | Description | Headings |
|---|---|---|---|---|---|
| smtp | 6 |  |
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| 3 | |
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| codes | 3 | |
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| wild | 2 | |
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| field | 2 | |
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Usability
Url
Domain : smtpfieldmanual.com
Length : 19
Favicon
Great, your website has a favicon.
Printability
We could not find a Print-Friendly CSS.
Language
Good. Your declared language is en.
Dublin Core
This page does not take advantage of Dublin Core.
Document
Doctype
HTML 5
Encoding
Perfect. Your declared charset is UTF-8.
W3C Validity
Errors : 0
Warnings : 0
Email Privacy
Great no email address has been found in plain text!
Deprecated HTML
Great! We haven't found deprecated HTML tags in your HTML.
Speed Tips
|
Excellent, your website doesn't use nested tables. |
|
Too bad, your website is using inline styles. |
|
Great, your website has few CSS files. |
|
Too bad, your website has too many JS files (more than 6). |
|
Perfect, your website takes advantage of gzip. |
Mobile
Mobile Optimization
|
Apple Icon |
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Meta Viewport Tag |
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Flash content |
Optimization
XML Sitemap
Great, your website has an XML sitemap.
| https://smtpfieldmanual.com/sitemap.xml |
Robots.txt
https://smtpfieldmanual.com/robots.txt
Great, your website has a robots.txt file.
Analytics
Great, your website has an analytics tool.
Google Analytics |
PageSpeed Insights
Device
Categories
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