A/B Pre-test Calculator by Speero

Name: A/B Pre-test Calculator by Speero
Author: https://speero.com/

Speero's A/B Pre-test Calculator helps you answer vital pre-test questions like MDE, sample size, duration, and more.

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Speero's A/B Pre-test Calculator is a powerful Chrome extension designed for marketers and data analysts to efficiently prepare for A/B testing. It helps you determine essential pre-test metrics such as minimal detectable effect (MDE), required sample size, and optimal test duration based on your website's traffic and conversion data.

Simply input the number of weekly sessions, conversions, and test variants, or connect directly to your Google Analytics 4 (GA4) account for automatic data retrieval. The calculator is preset for two variants with a 95% confidence level and 80% statistical power, but allows flexibility for various test scenarios. With features like filtering by page path and comparing data across multiple URLs, it streamlines your testing setup and ensures your tests are adequately powered and timely. Stay informed and confident in your A/B tests without leaving your browser tab using Speero's A/B Pre-test Calculator.

Extension

By:

https://speero.com/

Users:

1,000

Version:

1.4 Last updated: 2024-02-08

Creation date:

2023-08-09

Risk:

Permissions:

storage
identity

Host permissions:

https://accounts.google.com/o/oauth2/token

Size:

41.20KB

Email:

in*****@speero.com

URLs:

Website ,Privacy policy

Full description:

Source:

Chrome Web Store

Data ingested on:

2025-07-17

Ranking

# 29,323 ▼ 18

Other rankings

#3401 in Developer Tools ▲ 3 #116 in calculator keyword 35 ▲ 16 #137 in testing keyword 37 ▲ 17 #159 in effect keyword 22 ▲ 5

Extension safety

Risk impact

Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

A/B Pre-test Calculator by Speero requires a few sensitive permissions. Exercise caution before installing.

Risk impact analysis details

Critical Request access to the following domains: {{requestedDomains}}

Risk likelihood

Risk likelihood measures the probability that a Chrome extension may turn malicious. This is determined by the publisher and the Chrome extension reputation on Chrome Web Store, the amount of time the Chrome extension has been around, and other signals about the Chrome extension. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Chrome extension.

A/B Pre-test Calculator by Speero is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this extension.

Risk likelihood analysis details

High This extension has low user count. Unpopular extensions may not be stable or safe.
Low **** ********* *** ******* **** **** * ****** **** ***** ******** *** **** ****** ** ** ****** *** *****
Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****

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