
LetterStream
Click2Mail
Lob
PrintPigeon
Postsnap
PC2Paper
ClickSend
Send business letters online—one letter or a full batch. Upload a PDF or recipient CSV; Postmarkr verifies addresses, previews, prints, and mails US First-Class letters.

Decode and verify SSL/TLS certificates online. Extract X.509 details including issuer, validity, SAN, and fingerprint. Fast, secure, and browser-based.

Which is more popular?
Based on our record, Cert Decoder seems to be more popular. It has been mentioned 1 time since March 2021.
Website, pricing, platforms and company facts side by side.
|
|
|
|
|---|---|---|
| Website | postmarkr.com | certdecoder.com |
| Pricing | ||
| Platforms | — | |
| Listed in |
In their own words, as submitted to SaaSHub.


Postmarkr is an online print-and-mail service for sending business letters through USPS. Upload a finished PDF or import a recipient list, verify addresses, review a true-to-print preview and exact price, then Postmarkr prints and mails each letter via USPS First-Class Mail. Send one letter or a...
Cert Decoder is a free online tool that helps you decode X.509 SSL/TLS certificates in PEM format. It instantly shows important information like the issuer, expiry date, SAN entries, and fingerprint. All data is processed locally in your browser, so nothing is ever sent or stored elsewhere.
What each product offers, as listed by its team.


Possible disadvantages
Possible disadvantages
An editorial look at what each product does well and who it suits.


Overall verdict
Why this product is good
Recommended for
Overall verdict
Why this product is good
Recommended for
How often each product is chosen within a category, 0–100% relative to the other.


As answered by people managing Postmarkr and Cert Decoder.
Cert Decoder's answer:
I built certdecoder.com over the weekend for my own needs. Sometimes in my work, I need to verify and check certificate details.
Cert Decoder's answer:
certdecoder.com was built using just JavaScript and HTML—simple, fast, and with all processing happening locally in your browser, so no certificate data is sent to any server
Cert Decoder's answer:
certdecoder.com is primarily built for developers, sysadmins, cybersecurity enthusiasts, and DevOps engineers.
Cert Decoder's answer:
Simple, fast, and reliable. Some similar tools can’t even decode basic certificates. I rigorously tested my tool with many real-world certificates and covered several edge cases where competitors fall short.
Cert Decoder's answer:
certdecoder.com is primarily built for developers, sysadmins, cybersecurity enthusiasts, and DevOps engineers.
Share your experience with using Postmarkr and Cert Decoder. For example, how are they different and which one is better?
Recommendations tracked on public social media and blogs since March 2021.


Tracking Postmarkr since Feb 2026.
Why? Because I built certdecoder.com and couldn’t find a decent place to submit it. So I said screw it — I’ll build my own. With blackjack and hookers. - Source: dev.to / over 1 year ago
When comparing Postmarkr and Cert Decoder, you can also consider the following products.

Use our website to get your mailing out quickly. We offer First-Class Mail and postcards, Standard Mail also known as Marketing Mail, Certified Mail and FedEx overnight letters. Visit our website: LetterStream.com to get started today!
Compare LetterStream to Postmarkr or Cert Decoder:


A simple API to integrate print & mail solutions into your applications.
Compare Lob to Postmarkr or Cert Decoder:

Upload, print, and send letters online with PrintPigeon. Next-day delivery available. Save time and money on your postal tasks.
Compare PrintPigeon to Postmarkr or Cert Decoder:

Postsnap's iPhone app is the best, free postcard creator. Make & send real printed postcards, greeting cards, invitations and announcement cards using your own photos.
Compare Postsnap to Postmarkr or Cert Decoder:

PC2Paper allows you to send and receive postal mail ('snail mail') over the internet, through a web portal, print driver, e-mail gateway or API.
Compare PC2Paper to Postmarkr or Cert Decoder: