Live Traffic

The Live Traffic tab is one of the most important feature of Fiddler Everywhere. It display a short summary of each captured session (in the Live Traffic list) and provides functionalities to work with these sessions (via the Live Traffic toolbar and the Inspectors tabs). Fiddler Everywhere enables sessions saving and sharing.

A session (also mentioned as 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 in the course of processing the Session.

Live Traffic toolbar and list

Live Traffic Toolbar

The Live Traffic toolbar provides various functionalities like streaming mode, decoding content, filtering by 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


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 enable/disable the streaming mode.

    Stream Toggle button

    Streaming mode is useful for low-level network timing scenarios (for example, by design some browsers will parse partially-downloaded HTML, and 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 audo or video streams. These kind of never-ending streams can't be buffered by Fiddler Everywhere.


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

  1. Click on the Toggle button to enable/disable decoding the encoded content.

    Decode Toggle button

Example HTTP response with Decode toggled to OFF Decode OFF

Example HTTP response with Decode toggled to ON Decode ON


Use Filter to apply advanced 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 windows allow you to set specific criteria that will filter the captured traffic. Set the filter rules and click Apply.

    Advanced filters popup


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

  1. Click on the Save button.

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

    Save prompt window

  3. The current sessions entry appears in 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 colaboration and Fiddler Everywhere provides several options to export and share sessions:

This article demonstrates how to share sessions using the first two options. See the linked articles for examples on how to use exporting or sharing via the context menu.

Share Sessions

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

    Saving before traffic coulod be shared

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

    Share prompt window

To share Previosly Saved Sessions

  1. Double-click on the saved sessions entry from Sessions list.

  2. The selected entry opens in a new tab. Click on the Share button.

    Loading previosly saved sessions

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

Remove All

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

Live Traffic List

The Live Traffic is an essential feature of Fiddler Everywhere - it displays a list of web sessions with 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 Columns

Certain key information is displayed in the columns of the 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 request (GET, POST, 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 Field for showing the custom comments added by you (or the author of a shared session).

See a detailed explanation for the values in each column in the View Live Traffic Summary article.

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 recust into the composer windows where it can be editted 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 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 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 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 options are to select parent, children, and duplicate sessions.

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


Use the Copy context menu option to place a 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 autoresponder rule for the selected sessions.

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