ZeroSSL
Ranked 2 of 3 certificate authorities by recommenders
Free ACME certificate service with unlimited certs and wildcard support, often used as an alternative to Let's Encrypt. Critics question its free-tier limits, pricing jumps, and missing company and privacy information.
Free ACME certificate service with unlimited certs and wildcard support, often used as an alternative to Let's Encrypt. Critics question its free-tier limits, pricing jumps, and missing company and privacy information.
22 people gave an opinion
- recommend it
- 12
- criticize it
- 10
- approval share
- 55%
Recommended in 4 of 13 months
- November 2025: not recommended
- December 2025: recommended
- January 2026: not recommended
- February 2026: recommended
- March 2026: not recommended
- April 2026: not recommended
- May 2026: recommended
- June 2026: recommended
- July 2026: not recommended
- August 2026: not recommended
- September 2026: not recommended
- October 2026: not recommended
- November 2026: not recommended (month in progress)
Why it doesn’t carry the badge
- 12 people recommend itNeeds 10 or more, met.
- 1.2 recommenders for every criticNeeds 2 to 1 or better, not met.
- Recommended in 4 of 13 monthsNeeds 4 or more, met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Free certificates via ACME
“you get basically the same functionality as with LetsEncrypt for free, including wildcard certs”
Comment from 9 Jun 2026 in “Let's Encrypt bans certificate usage in any US sanctioned territory [pdf]” “they also have a free ACME endpoint which is totally unlimited and does support wildcards”
Comment from 18 Feb 2026 in “Google Public CA is down” “free 90-day certs via ACME, also has a web UI for cert management”
Comment from 19 Jun 2026 in “Let's Encrypt has been down most of today” - Comment from 2 Dec 2025 in “Decreasing Certificate Lifetimes to 45 Days”
Wildcard certificates supported
“you get basically the same functionality as with LetsEncrypt for free, including wildcard certs”
Comment from 9 Jun 2026 in “Let's Encrypt bans certificate usage in any US sanctioned territory [pdf]” “they also have a free ACME endpoint which is totally unlimited and does support wildcards”
Comment from 18 Feb 2026 in “Google Public CA is down” Similar to Let's Encrypt
“acme.sh has been using it as the default for the last few years. As I understand it, it basically offers the same as Let's Encrypt.”
Comment from 2 Dec 2025 in “Decreasing Certificate Lifetimes to 45 Days” “you get basically the same functionality as with LetsEncrypt for free, including wildcard certs”
Comment from 9 Jun 2026 in “Let's Encrypt bans certificate usage in any US sanctioned territory [pdf]” Default in Caddy and acme.sh
“Zerossl is integrated with Caddy by default and there’s no indication from Caddy that you would only be able to renew the cert twice”
Comment from 2 Dec 2025 in “Decreasing Certificate Lifetimes to 45 Days” “acme.sh has been using it as the default for the last few years. As I understand it, it basically offers the same as Let's Encrypt.”
Comment from 2 Dec 2025 in “Decreasing Certificate Lifetimes to 45 Days”
What people warn about
Each mark is one comment
Free tier limited to three certs
“ZeroSSL advertised for free 3 certificates with no multiple names or wild cards. The next plan was $180 yearly.”
Comment from 9 May 2026 in “Lets Encrypt Stopping Issuance for Potential Incident” “suggests a 3-cert limit on the free tier, as well as a huge influx of expected spam”
Comment from 2 Dec 2025 in “Decreasing Certificate Lifetimes to 45 Days” Pricing jumps and upsells
“ZeroSSL advertised for free 3 certificates with no multiple names or wild cards. The next plan was $180 yearly.”
Comment from 9 May 2026 in “Lets Encrypt Stopping Issuance for Potential Incident” “something scummy about upsells there a few years back”
Comment from 10 Dec 2025 in “10 Years of Let's Encrypt” “That's a pretty steep increase.”
Comment from 9 Jun 2026 in “Let's Encrypt bans certificate usage in any US sanctioned territory [pdf]” Unclear company info and privacy policy
“without a proper company info page and privacy policy I wouldn't consider it anywhere near a "good alternative"”
Comment from 9 Jun 2026 in “Let's Encrypt bans certificate usage in any US sanctioned territory [pdf]” “require you to have an account (which means you're at their mercy)”
Comment from 15 Dec 2025 in “Upcoming Changes to Let's Encrypt Certificates”
Other certificate authorities people recommend
The two most recommended other certificate authorities, with the same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.
| Product | Recommend | Criticize | Approval | Months | Owned | Badge |
|---|---|---|---|---|---|---|
| Let's Encrypt | 172 | 89 | 66% | 12 | 5.5 yrs6 owners | — |
| ZeroSSLThis page | 12 | 10 | 55% | 4 | — | — |
| Sectigo certificate | 5 | 9 | 36% | 3 | — | — |
What people said
21 of the 24 comments that mention it, newest first. Each links to the original comment.
“not a good look when everyone needs to be automating certificate renewal”
“this has been down for a few days in a row now”
“free 90-day certs via ACME, also has a web UI for cert management”
“ZeroSSL from Austria also has a limited free tier.”
“you get basically the same functionality as with LetsEncrypt for free, including wildcard certs”
“I'm pretty happy so far. I have a paid account to support them”
“There was some subtle issue with ZeroSSL's implementation of ACME that I ran into”
“That's a pretty steep increase.”
“without a proper company info page and privacy policy I wouldn't consider it anywhere near a "good alternative"”
“ZeroSSL advertised for free 3 certificates with no multiple names or wild cards. The next plan was $180 yearly.”
“Change your config to ZeroSSL or another free ACME provider?”
“ZeroSSL should also be drop in”
“they also have a free ACME endpoint which is totally unlimited and does support wildcards”
“require you to have an account (which means you're at their mercy)”
“LE has some gnarly rate limiting rules, so I use ZeroSSL. Works out great for my purposes.”
“something scummy about upsells there a few years back”
“The "ACME Certificates" are free and unlimited.”
“Zerossl is integrated with Caddy by default and there’s no indication from Caddy that you would only be able to renew the cert twice”
“suggests a 3-cert limit on the free tier, as well as a huge influx of expected spam”
“acme.sh has been using it as the default for the last few years. As I understand it, it basically offers the same as Let's Encrypt.”
“constant 60 days rotation with LE or ZeroSSL caused endless support heartache”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.