Is kotl.in secure (HTTPS)?

Yes. kotl.in uses TLS 1.3 with a certificate issued by Amazon, valid until Oct 4, 2026.

Hosting provider information for kotl.in is not available yet.

What is kotl.in's SEO score?

kotl.in scored 75/100 for SEO in the latest analysis (fair).

What is kotl.in's overall website score?

kotl.in has an overall SiteGraph score of 86/100, combining SEO, performance, security, and accessibility.

kotl.in

Kotlin Programming Language

Last scanned Jul 26, 2026, 10:54 AM

Overall score

Great

Summary

Kotlin is a concise and multiplatform programming language by JetBrains. This website uses Next.js behind CloudFront CDN. SEO is good (75/100) and accessibility is excellent (100/100). Security scores good (75/100) and performance excellent (100/100). Top issue: Multiple H1 headings found.

Kotlin is a concise and multiplatform programming language by JetBrains. Enjoy coding and build backend, mobile, web, and desktop applications efficiently.

Top issues to fix

8 issues found · 2 high priority

Missing Strict-Transport-Security header
Security
Add HSTS so browsers always use HTTPS — this closes the protocol-downgrade attack window.
Missing Content-Security-Policy header
Security
Add a CSP to control which sources can run scripts — the strongest single defense against XSS.
Missing X-Content-Type-Options header
Security
Add X-Content-Type-Options: nosniff to stop MIME-sniffing attacks.
Multiple H1 headings found
SEO
Keep a single H1 per page and demote the others to H2/H3.
No structured data (JSON-LD) found
SEO
Add JSON-LD (Organization, Article, Product…) to become eligible for rich results.
robots.txt not found
SEO
Publish /robots.txt with a Sitemap: directive to guide crawlers.

+2 more issues — details in the sections below.

SEO

4 issue(s) found

100

Performance

590 ms

Security

HTTPS & header checks

100

Accessibility

0 issue(s) found

Not enough scan history yet to show a trend — check back after this site has been re-scanned a few more times.

Organization

Company details published in this site's own structured data.

Kotlin is a concise and multiplatform programming language by JetBrains. Enjoy coding and build backend, mobile, web, and desktop applications efficiently.

YouTube X (Twitter)YouTube

Meta tags

Title: Kotlin Programming Language
Description: Kotlin is a concise and multiplatform programming language by JetBrains. Enjoy coding and build backend, mobile, web, and desktop applications efficiently.
Canonical: https://kotlinlang.org/
Language: en
Charset: utf-8
Viewport: width=device-width, initial-scale=1
Robots meta
Manifest

Technologies

Detected frameworks, languages, and tools.

Next.js

Hosting & CDN

Hosting provider: —
CDN provider: CloudFront
IP address: —
ASN: —

DNS records

Type	Value
A	—
AAAA	—
MX	—
TXT	—
NS	—
CAA	—
CNAME	—
IPv6 support	No

TLS / SSL certificate

Version: TLS 1.3
Issuer: Amazon
Subject: kotlinlang.org
Valid from: Sep 6, 2025
Valid to: Oct 4, 2026
Days until expiry: 68
SAN domains: kotlinlang.org, www.kotlinlang.org, kotlinlang.prod.kotlin-aws.intellij.net, www.kotlinlang.prod.kotlin-aws.intellij.net

Security headers

Strict-Transport-SecurityMissing
Content-Security-PolicyMissing
X-Frame-OptionsEnabled
X-Content-Type-OptionsMissing
Referrer-PolicyEnabled
Permissions-PolicyMissing

Compression: gzip · 0 cookie(s) observed

Content & assets

Headings

H1 5 · H2 7 · H3 12

Links

32 internal · 31 external · 20 broken

Images

45 total · 0 missing alt

Scripts / Styles

21 scripts · 5 stylesheets

JS / CSS size

221 B · 2.3 KB

Page size

244 KB

Robots.txt & Sitemap

robots.txt: Not found
Disallow rules: 0
sitemap.xml: Not found
URLs in sitemap: 0

SEO issues

Multiple H1 headings found
No structured data (JSON-LD) found
robots.txt not found
sitemap.xml not found

Scan details

Requested URL: https://kotl.in
Final URL: https://kotlinlang.org
HTTP status: 200
HTTP version: HTTP/2
Response time: 585 ms
HTML size: 244 KB
Redirect chain: https://kotl.in → https://kotlinlang.org

See something wrong on this report? Request a correction

Frequently asked questions

What technology does kotl.in use?: kotl.in is built with Next.js.
Is kotl.in secure (HTTPS)?: Yes. kotl.in uses TLS 1.3 with a certificate issued by Amazon, valid until Oct 4, 2026.
Who hosts kotl.in?: Hosting provider information for kotl.in is not available yet.
What is kotl.in's SEO score?: kotl.in scored 75/100 for SEO in the latest analysis (fair).
What is kotl.in's overall website score?: kotl.in has an overall SiteGraph score of 86/100, combining SEO, performance, security, and accessibility.