HAR Viewer
HAR Viewer (HTTP Archive Viewer) is an online tool visualizing HTTP Archive (HAR) files produced by HTTP tracking tools. These files contain a log of HTTP client/server conversation and can be used for an additional analysis of e.g. page load performance.
Check out online
Report issues or suggestions here
User interface of this tool is composed from the following tabs (*):
- Home - Paste content of a log file into the text box in this tab.
- Preview - Switch to this tab if you want to see visualised HTTP traffic.
- HAR - Use this tab to see structure of the input JSON data as an expandable tree.
- About - About the tool.
- Schema - Explore format of the input log in this tab.
* Visibility of individual tabs can be customized
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![]() $.log.entries[={page: pageref, time: time, cache: cache}] |
Create HAR using Firebug
One of the tools you can use to create a HAR log is Firebug. You have to also install Firebug extension called NetExport.
HAR Viewer API
HAR Viewer can be customized through available APIs. You can remove existing tabs you don't need when embedding HAR Viewer in your system, hide some toolbar buttons that are not necessary in your production releases, etc.
Resources
HTTP Archive 1.2 spec : http://groups.google.com/group/http-archive-specification
HAR Viewer Issue List: https://github.com/janodvarko/harviewer/issues
HAR Viewer Docs: http://code.google.com/p/harviewer/w/list
HAR Viewer Online: http://www.softwareishard.com/har/viewer/
NetExport (extension): http://www.softwareishard.com/blog/netexport/
Online Log Files
HAR Viewer supports JSONP and so, it's possible to load log files from different domains. This allows linking your online logs and preview them automatically within the viewer. See live example.
- The Content of a *.harp is HAR enclosed within a callback function.
onInputData({ "log": { ... } })
- The link displaying a *.har file (using the viewer) must specify URL of the file in an inputUrl parameter.
http://www.softwareishard.com/har/viewer/?inputUrl=http://www.example.com/netData.har
- A custom name of the callback function can be specified in a callback parameter (by default it's onInputData).
http://www.softwareishard.com/har/viewer/?inputUrl=http://www.example.com/netData.har&callback=onInputData
HAR Viewer For Chrome
HAR Viewer is also distributed as a Chrome packaged app on the Chrome store (source available).
Projects Embedding HAR Viewer
HAR Viewer is an open source released under BSD License and it's already incorporated in to several projects (see the list below). Check also HAR Adopters page.
Did you also included HAR Viewer into your project? Please, let me know and I'll update the list!
HAR Viewer Sponsors
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List of all HAR Viewer adopters
Ruby HAR Library
Ruby library to work with and view HTTP archives. This library includes HAR Viewer, which can be launched through a har command. This command allows launching a local HAR Viewer from the command line:
har /path/to/some.har
GTmetrix
GTmetrix can help you develop a faster, more efficient, and all-around improved website experience for your users. Integrates Page Speed, YSlow, HAR Viewer.
Mobile Test Site
Mobile test site for 5o9 Inc. Are interested in android browser performance analysis? See this site that shows mobile HAR reports.
Blaze.io
Blaze Mobile Performance Test uses real iPhone and Android agents to conduct a performance analysis of browsing your website on a mobile device.
Show Slow
Show Slow is an open source tool that helps monitor various website performance metrics over time.
WatchMouse
WatchMouse uses HAR as the internal storage and HAR Viewer for displaying captured data as a waterfall.
Browser Mob
BrowserMob Provides FREE Website Monitoring and Load Testing.
CrossBrowserTesting
Cross Browser Testing is recording network activity during live tests and using HAR Viewer to display results.
AlertFox
AlertFox is a revolutionary new browser-based monitoring service that is capable of keeping tabs on the function and performance of all websites, even those that use AJAX, Flash, Flex, and Silverlight.
$10.00 suggested