When comparing Postman vs elasticsearch-gui, the Slant community recommends Postman for most people. In the question“What are the best Elasticsearch GUI clients?” Postman is ranked 1st while elasticsearch-gui is ranked 2nd.
Ranked in these QuestionsQuestion Ranking
Pro Flexible and powerful
Can easily add/remove parameters, headers, tests and more. Displays all the info you would want in a partitioned way so you can track exactly what you want. Able to save request and run them in bulk for testing real-user scenarios very efficiently.
Pro Clear interface
The interface of the program is clean and intuitive. Almost all features are accessible through a single click.
Pro Two versions of apps are available
Packaged app and an in-browser app are available for Google Chrome.
Pro Runs as AngularJS client
Can use ElasticSearch as a plugin for AngularJS platform.
Pro Connects to each ES instance (html-based)
Pro Displays basic cluster information
Shows name, number of nodes, number of data nodes, active primary shards, active shards, relocating shards, initializing shards, and unassingned shards.
Pro Allows to explore your ES index
Provides different ways to explore your index, from keyword-based search to facets or filtering options in the query.
Pro Free and open source
Elasticsearch-gui is a free and open source GUI client for ElasticSearch. It's released under the Apache 2.0 licence.
Since it's web-based, all you need to run and access the GUI client is a web browser.
Con Resource hog
Con Doesn't work right with localized queries
Con Does not support Proxy authentication
Con Looks like it's been abandoned
No updates since 2016 (it's late 2018, at the time of writing).