stemline.com website review

About 1.1 MB of JavaScript is downloaded but never used on this page. Google estimates it would make the page about 7.8 s faster on a phone.

24 files block the first paint until they finish downloading. Deferring or inlining them could save about 4.7 s.

About 268 KiB of CSS is downloaded but never applied on this page. Google estimates it would make the page about 1.7 s faster on a phone.

5 images could be 196 KiB smaller with modern formats (WebP or AVIF) and sizes that fit a phone screen. Google estimates it would make the page about 1.3 s faster on a phone.

217 KiB could be saved by minifying JavaScript.

Your mobile performance score is 55 (desktop: 59). Pages that score under 90 lose visitors before the first paint.

7 third-party services load with your homepage (Google CDN, Optanon and Google Tag Manager and others), adding 1.4 MB and 615 ms of main-thread time.

Google CDN costs a phone 313 ms of main-thread work and 734 KiB of downloads while your page loads. Loading it after the page is usable, or only on the pages that need it, takes that off the critical path.

A phone's processor spends 2.3 s on main-thread work while loading, 1.4 s of it running JavaScript. Above 2 s, taps and scrolls feel sluggish.

Google Tag Manager costs a phone 131 ms of main-thread work and 360 KiB of downloads while your page loads. Loading it after the page is usable, or only on the pages that need it, takes that off the critical path.

7 files are served with short cache lifetimes, so returning visitors download them again (65 KiB).

24 KiB could be saved by minifying CSS.

Web fonts hide text while they load. Setting font-display: swap shows text immediately (about 100 ms).

9 long tasks block the main thread while loading, the longest for 100 ms. During a long task the page ignores taps.

Polyfills for old browsers add 22 KiB JavaScript that modern phones do not need.

Critical files load one after another instead of in parallel (3 chains). Preconnecting to key origins and preloading the hero image shortens the chain.

Scripts make the browser recalculate the layout repeatedly while the page loads, which wastes processor time on phones.

Real Chrome users on phones do not pass Google's Core Web Vitals on this page (28-day field data from the Chrome UX Report (opens in a new tab)). Google uses this in ranking.

The first text or image appears after 13.1 s on a phone. Good is under 1.8 s.

Your largest element takes 20.8 s to render on a phone. Google's threshold for “good” is 2.5 s. The largest element is the element shown below.

The page becomes fully interactive after 21.0 s. Good is under 3.8 s.

Visually, the page fills in at 13.1 s (Speed Index). Good is under 3.4 s.

Real visitors wait 2.8 s for the largest content to appear (75th percentile). Good is under 2.5 s.

Real visitors see the first content after 2.0 s (75th percentile). Good is under 1.8 s.

1 image have no width and height attributes, so the layout jumps as each one loads.

Over the last 25 four-week periods to 2026-10-24, real Chrome visitors' tap response (inp) went from 81 ms to 81 ms at the 75th percentile (Chrome UX Report (opens in a new tab) history).

Over the last 25 four-week periods to 2026-10-24, real Chrome visitors' largest content (lcp) went from 2.1 s to 2.1 s at the 75th percentile (Chrome UX Report (opens in a new tab) history).

Your homepage downloads 3.5 MB in 81 requests on a phone: scripts 2.1 MB (34), other files 398 KiB (15) and images 394 KiB (11). Under 2 MB keeps phones on slow connections fast.

2 images (150 KiB) are JPEG, PNG or GIF. The same pictures as WebP or AVIF are usually much smaller at the same quality, and every current browser shows them.

2 images further down the page (141 KiB) download before anyone scrolls to them. Adding loading="lazy" lets the first screen load first.

By the Sustainable Web Design model, a visit to your homepage emits about 1.00 g of CO₂e: 119.5 kg a year at 10,000 visits a month. It scales with page weight, so every byte cut lowers it.

11 text elements don't have enough contrast against the background to read easily, especially outdoors on a phone.

4 tap targets are too small or too close together to hit reliably with a finger.

1 form field has no label, so screen readers announce an empty box and autofill guesses.

No meta description, so Google writes its own snippet from whatever text it finds.

There is no <h1>, so neither visitors nor Google get a clear main headline.

Your title is only 28 characters: “Home - Stemline Therapeutics”. Between 30 and 65 characters leaves room to say what you do and for whom.

No Open Graph image (also missing: og:description), so links shared on LinkedIn, Slack or Facebook show no preview picture.

4 links use generic text like “click here” or “learn more”, which tells Google nothing about the page behind them.

The homepage links to 28 pages on stemline.com and 5 external pages.

Your Organization JSON-LD is missing sameAs (social profiles), description and contact details. These are the facts AI assistants use to describe a business and to tell it apart from others with a similar name.

There is no https://stemline.com/llms.txt, a short Markdown guide to your key pages for AI tools (llmstxt.org). It is optional and few AI tools read it yet, so treat it as a cheap extra.

https://stemline.com/about, https://stemline.com/about/management, https://stemline.com/about/business-development, https://stemline.com/product-pipeline, https://stemline.com/pipeline/scientific-presentations-2 and https://stemline.com/pipeline/clinical-trials-2 and 8 others have no meta description, so Google writes the search snippet from whatever text it finds.

https://stemline.com/about, https://stemline.com/about/business-development, https://stemline.com/product-pipeline, https://stemline.com/expandedaccess, https://stemline.com/contact and https://stemline.com/contact/reporting-concerns have no <h1> headline, so visitors and search engines get no clear main topic.

https://stemline.com/contact/reporting-concerns has under 150 words in the HTML. Thin pages rarely rank; if the text loads with JavaScript, crawlers that don't run it see even less.

We fetched 14 pages linked from your homepage and read each the way a search engine does.

1 error was logged to the browser console while the page loaded, for example “Uncaught TypeError: Cannot read properties of undefined (reading 'toLowerCase')”.

Large scripts ship without source maps.

No testimonials, customer logos, ratings or customer counts on the homepage: nothing tells a new visitor that others already trust you.

No phone number or email link on the homepage, so ready-to-buy visitors have one fewer way to reach you.

There is no form on the homepage, so every lead has to click through to another page first.

No guarantee or risk reducer (money-back, free trial, no credit card) is mentioned, which is often what tips a hesitant visitor.

The homepage carries about 300 words of visible text.

Before a visitor clicks anything, the page loads Google Analytics and Google Tag Manager (measured from a US location before any click). A consent tool (OneTrust) is installed; check it blocks these until visitors agree where the law requires it.

Opening the homepage sets 31 cookies (measured from a US location before any click).

Loading the homepage contacts 8 hosts run by other companies (fonts, scripts, analytics, ads), each of which sees the visitor's IP address.