Technology & Software
SMTP Codes
A comprehensive reference guide to SMTP response codes and error messages from major email providers.
Visit smtp.codes ↗- Extension
- .codes
- Discovered
- 6/18/2026
- Domain registered
- Domain age
- Newly registered
- Language
- English
Why it's here
- ✓ The domain resolves and the homepage loads
- ✓ Not parked, for sale or a placeholder page
- ✓ Real content: at least 400 characters of text and several internal pages
- ✓ Passed an AI review for quality and safety
Why it ranks
25 Emerging
- Brand (25%)0
Not a known brand
- Popularity / traffic (20%)10
Not in Tranco top 1M
- Authority / backlinks (15%)unknown
Not checked yet
- Marketing of the domain (15%)25
Open-source developer reference site with GitHub collaboration links.
- Content quality (10%)78
78/100
- Design & build (5%)75
75/100
- Domain age (10%)36
3.6 years since registration
A clean, functional, and very handy reference directory of SMTP status codes with great exact-match TLD usage.
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