Live Traffic Tab

The Live Traffic tab is is an essential feature of Fiddler Everywhere. It display a summary of each captured session (in the Live Traffic list) and provides functionalities to work with these sessions (via the Live Traffic toolbar, the Inspectors tabs, and the interconnected Auto Responder. The section also enables sessions saving and sharing, editing issued requests, marking, commeting sessions, and applying Auto Responder rules.

A Session (also mentioned as a web session) represents a single transaction between a client and a server, sometimes known as request/response pair. Each Session appears as a single entry in the Live Traffic (refer to the images below). Each Session object has a Request and a Response, representing what the client sent to the server and what the server returned to the client. The Session object also maintains a set of Flags that record metadata about the Session and a Timers object that stores timestamps logged during the Session processing.

Live Traffic toolbar and list

Live Traffic Toolbar

The Live Traffic toolbar provides various functionalities like streaming mode, decoding content, filtering by different criteria, saving, and sharing sessions.

Live Traffic Toolbar

To start capturing, you need to enable Live Traffic switch to Capturing mode. Use the off switch state to pause the traffic capturing.

Enabling Live Traffic

The Live Traffic toolbar provides the following functionalities:


By default, Fiddler Everywhere uses buffering mode, which means that the responses are fully collected before any part is sent to the client. Buffering alters the responses (for example, an image won't begin to download until the containing page download is complete). With streaming mode, the server's responses are immediately returned to the client as it is downloaded. In streaming mode, tampering with the response body is not possible.

  1. Click on the Stream button to toggle between the streaming and buffering modes.

    Stream Toggle button

    Streaming mode is useful for low-level network timing scenarios (for example, by design, some browsers will parse partially-downloaded HTML. That would start downloading external resources in parallel before the remote server has finished delivering the content).

    Buffering mode vs Streaming Mode

    Streaming mode is also useful in cases where a site delivers audio or video streams. These kinds of never-ending streams can't be buffered by Fiddler Everywhere.


Use the Decode toggle button to remove all HTTP content and Transfer encoding from requests and responses.

  1. Click on the Toggle button to toggle the decoding of an encoded content.

    Decode Toggle button

An example for HTTP response with Decode toggled to OFF Decode OFF

An example for HTTP response with Decode toggled to ON Decode ON

Advanced Filters

Use the Advanced Filters to apply filters based on the Request and Response headers. Only sessions that are covering the filter criteria will appear in the Live Traffic list.

  1. Click on the filter button to open the advanced filters popup windows.

    Filter sessions button

  2. The Advanced Filters window allow you to set specific criteria that will filter the captured traffic. Set the filter rules and click Apply.

    Advanced filters popup

Note: Alternatively, you can apply filters through the more option on each Live Traffic column (e.g., apply a filter for Host column).

Clear All Filters

Use the Clear All Filters to reset all filters applied by Advanced Filters and filters applied for each column (see the columns section)

Clear All Filter  button


Use the Save button to save sessions for later use or to prepare sessions for sharing.

  1. Click on the Save button.

    Save button

  2. A Save Sessions prompt windows appears. Enter a valid name and click Save.

    Save prompt window

  3. The current entry (of sessions) appears in the Sessions list.

The Save button will automatically save all captured traffic. If you want to save only specific sessions, you can select the wanted sessions and use the context menu for advanced save options.


Sharing sessions greatly improves collaboration, and Fiddler Everywhere provides several options to export and share sessions:

This article section demonstrates how to share sessions using the first two options. See the linked articles for examples on how to use other sharing functionalities with Fiddler Everywhere.

The toolbar comes with a Share button that will save the currently displayed sessions (captured from Live Traffic) in a file and then shares them through email (provided explicitly).

  1. Click on the Share button.

    Share button

  2. The Save Session prompt window appears. You need to save the sessions before they could be shared.

    Saving before traffic could be shared

  3. The Share Sessions prompt window appears. Enter a valid email (mandatory) and notes (optional) and click on the Share button.

    Share prompt window

Remove All

The Remove All button is removing all currently captured traffic from the Live Traffic list. To remove specific selected sessions, use the context menu

Remove All button

Live Traffic List

The Live Traffic list is an essential feature of Fiddler Everywhere - it displays a list of web sessions with a summary of each session that the Fiddler Everywhere client has captured.

Live Traffic

Many operations begin by selecting one or more entries in the Live Traffic and then activating other features.

  • To select more than one Sessions, hold the Ctrl (Command on Mac) or Shift keys while clicking on the desired rows.
  • Double-click or press Enter (Return on Mac) to activate the default inspectors for a single selected Session.

When the Inspectors are activated, they will automatically decide which Inspector is best suited to display the selected session's request and response.

Live Traffic List Icons

The Live Traffic List uses the following icons to provide additional context for each recorded session:

  • Generic document icon - Represents a generic successful response.
  • Uploading icon - Uploading content for a session in progress (the request is being sent to the server).
  • Upload paused icon - Uploading paused for session in progress.
  • Downloading icon - Downloading content for session in progress (the response is being read from the server).
  • Downloading paused icon - Downloading paused for session in progress.
  • Aborted icon - The session was aborted by the client, Fiddler, or the Server.
  • Error icon - The response was a server error.
  • Unauthorized icon - The response returned status code 401 Unauthorized.
  • Redirect icon - The response returned status code 300, 301, 302, 303 or 307 redirect.
  • WebSocket tunnel icon - A tunnel used for WebSocket traffic.
  • HTTPS tunnel icon - The request used the HTTP CONNECT method - establishes a tunnel used for HTTPS traffic.
  • RPC tunnel icon - A tunnel used for RPC traffic.
  • No Content icon - No content loaded.
  • Not modified icon - Not modified.
  • Partial content icon - Partial content.
  • Image icon - The response was an image.
  • JavaScript icon - The response was a JavaScript file.
  • CSS icon - The response was a CSS file.
  • HTML icon - The response was an HTML file.
  • Flash icon - The response was a Flash file.
  • XML icon - The response was an XML file.
  • Silverlight icon - The response was a Silverlight file.
  • Audio icon - The response was an audio file.
  • Video icon - The response was a video file.
  • Font icon - The response was a font file.
  • JSON icon - The response was a JSON file.
  • POST method icon - The request used the POST method.

Live Traffic Columns

Certain key information is displayed in the columns of Live Traffic, including:

  • # - An identification number generated by Fiddler Everywhere
  • Result - The status code from the response
  • Protocol - The protocol (HTTP/HTTPS/FTP) used by the Session
  • Host - The hostname and the port of the server to which the request was sent
  • URL - The URL path, file, and query string from the request
  • Method - The HTTP Method used by the made request (GET, POST, PUT, etc.)
  • Body - The number of bytes in the response body
  • Caching - Values from the Response's Expires and Cache-Control headers
  • Content-Type The Content-Type header from the response
  • Process The local OS process from which the traffic originated
  • Comments A field for showing the custom comments added by you (or the author of a shared session).

Each column comes with a more button (three vertical dots), which opens a popup with Filter and Columns submenus.

Use the Filter submenu to apply filters for the currently selected column only (e.g., filter all the traffic by host name or by a specific status code). Columns with active filters will have a blue filter indicator. You can clear active filters via the Filter popup (for the filtered column) or use the global Clear All Filters button.

Filter context submenu

Use the Columns submenu to select which column should be visible in the Live Traffic list. By default all columns are visible.

Columns context submenu

Refer to the KB article "How to View Web Session Summary" for detailed information about each column type.

Live Traffic Context Menu

The context menu for the Live Traffic exposes several actions that can be applied for a Session or multiple Sessions. To show the context menu, press right-click on Windows (Control + mouse click on Mac).

Live Traffic context menu

Edit in Composer

The context menu option Edit in Composer loads the selected request in a new Composer window where it can be edited, saved (for later usage and sharing), and reissued.


The context menu option Save provides the means to save selected sessions. The saved sessions will appear in the Sessions (the list to the left of Fiddler Everywhere interface) from where they can be re-opened later, exported, and shared.

  • Selected sessions - Saves all selected sessions. Keyboard shortcut: S.
  • Unselected sessions - Saves all unselected sessions. Keyboard shortcut: Shift + Cmd + S (Mac) Shift + S (Windows).
  • All Sessions - Saves all captured traffic (Keyboard shortcut: S). Keyboard shortcut: Cmd + S (Mac) Ctrl + S (Windows).

All three options will display a save prompt.

  1. Select the sessions, open the context menu, and click on the Save option.
  2. Enter your session name and click Save
  3. The saved sessions are immediately loaded in the Sessions list.
  4. Double-click on the saved session to load it in the Live Traffic list.

Alternatively, you can save all captured traffic via the Save button from the toolbar


The context menu option Share enables the sharing of sessions. Before any session is shared, it is saved as an entry in the Sessions list. Then the entry can be shared via email.

  • Selected sessions - Saves & shares all selected sessions.
  • Unselected sessions - Saves & shares all unselected sessions.
  • All Sessions - Saves and shares all captured traffic.

All three options will initially display a save prompt and then a share prompt window.

  1. Select the sessions, open the context menu, and click on the Share option.
  2. The selected sessions are being saved. Enter your session name and click Save and proceed
  3. The share screen prompt window appears. Enter valid email and optionally add notes. Once ready, click Share.

Fiddler Everywhere has a quota limit for creating snapshots of sessions. Refer to the FIddler Everywhere plans page for details.

Alternatively, you can share captured traffic via the Share button from the toolbar


Use the Remove context menu options to delete sessions from your Live Traffic list.

  • Selected sessions - Removes all selected sessions. Keyboard shortcut: Cmd + Back (Mac), Del (Windows).
  • Unselected sessions - Removes all unselected sessions. Keyboard shortcut: Shift + Cmd + Back (Mac), Shift + Del (Windows).
  • All Sessions - Removes all captured traffic. Keyboard shortcut: Cmd + X (Mac), Ctrl + X (Windows).


Use the Comment context menu option to add comments for the associated sessions.

  1. Select the sessions, open the context menu, and click on the Comment option. Keyboard shortcut: M.
  2. A Comment dialog appears. Enter the comment and click Ok.
  3. The text is added to the comment field for the selected sessions.


Use the Mark context menu option to apply different colors or to strikeout selected sessions.

  1. Select the sessions, open the context menu, and click on the Mark option.
  2. Click on the preferred marking style to apply it.


Use the Replay context menu option to replay previously captured sessions. Keyboard shortcut: R.


Use the Select context menu option to select sessions that are directly related to the currently selected session. The possibilities are to choose parent, children, and duplicate sessions.

  • Parent request Selects the session that is a parent of the currently selected session. Keyboard shortcut: P
  • Children requests Select the sessions that are children of the currently selected session. Keyboard shortcut: C
  • Duplicate request Selects the session that is a duplicate to the currently selected session. Keyboard shortcut: D


Use the Copy context menu option to place session information in the clipboard. The copied information options are:

  • URL Provides the session URL. Keyboard shortcut:Cmd + U (Mac), Ctrl + U (Windows)
  • FUll Summary Provides verbose session details. Keyboard shortcut: Cmd + C (Mac), Ctrl + C (Windows)

Example for copying URL

Example for copying full info

277 200 HTTP    /fiddler-everywhere/images/livetraffic/websessions/websessions-list-share-options.png   GET 207,094 private, max-age=0, proxy-revalidate, no-store, no-cache, must-revalidate   image/png; charset=utf-8        

Add New Rule

Use the Add new rule option to apply an Auto Responder rule for the selected sessions.

Additional Resources

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