Website tools / Calibre App
Calibre App
Calibre combines real user monitoring, Google CrUX data, and synthetic page speed tests so your team always knows where performance stands and what to fix.
Where it stands
4.2 / 5
Signals score
Not a hands-on test
Based on 2 of 3 signals
- Website health5 / 5 · weight 50%
Measured from the tool's public website
- Facts stated4.2 / 5 · weight 30%
How many of the five facts the tool's own pages state
Built only from what we can measure or quote without using the tool. How ranking works
Rank by signals
We have not run our own hands-on test on Calibre App yet. Facts checked 2026-11-01. How tests work
Disclosure: agathox makes some of the tools listed here. They are labelled and scored by the same method as every other tool.
Measured signals
5 / 5 · measured 2026-11-08Read automatically from Calibre App's public website: how reliable, secure, private and open the site is. This is not a test of how well the tool does its job. How this is measured
- Reliability5 / 5The page answered and finished downloading in 182 ms.
- Security5 / 55 of 5 protective headers set (strict-transport-security, content-security-policy, x-content-type-options, referrer-policy, x-frame-options).
- Privacy5 / 5No third-party tracking services found on the page.
- Transparency5 / 5Links a privacy policy; links a pricing page.
Community feedback
Not enough discussion yet: 4 classified comments from 2 threads. We need at least 12 from 2 threads.
- Positive
“I thought the same but was not excited, because Calibre is almost completely perfect already. If anybody reading this ever wants to convert ebooks from one format to another, or turn web pages into ebooks, or any such…”
Read in the thread - Positive
“We've been using calibre app on Vecteezy and its helped us keep track (and improve) our site performance. Its a great tool and continues to improve!”
Read in the thread
Threads: Calibre beta announced (2014, 20 comments) · Show HN: Calibre Test Profiles – Test your sites under real world conditions (2017, 17 comments)
- Free tier
- No permanent free plan is listed. The pricing page offers a 15-day free trial; trial limits are not stated.
- Paid plan
- Starter $75/month (5,000 Real User sessions, 5,000 Synthetic tests/month, 3 seats). Team $150/month (10,000 sessions, 15,000 tests/month, 10 seats). Company $1,500/month paid yearly (1,000,000 sessions, 50,000 tests/month, 50 seats). A monthly/annual toggle is shown; extra usage and seats cost more.
- Signup
- Trial and plans link to a sign-up page; whether an account is required is not explicitly stated.
- Watermark
- Not applicable.
- Where files go
- Servers and primary database are in the United States. Real user monitoring data is first processed at edge locations near the visitor, then sent to the US database. Retention: account info for the account's life plus 90 days; billing records 7 years; synthetic monitoring data for the subscription's duration; real user data 3-24 months as configured by the customer.
From the tool's own pages, checked 2026-11-01. Sources: Pricing, Privacy policy. Prices and limits change; check the tool before you rely on them.
Get an email if Calibre App changes
We check its official pages every week. If they change, we tell you, so you can see if the price or limits moved. No other email, and one click stops it.
Compare with: PageVitals
Are you the maker of Calibre App? Link to this page
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<a href="https://agathox.com/tools/calibre-app">Calibre App on agathox: compared and tested</a>
Tasks and scores
- Website speed testNot tested yet
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