New in version

July 24th, 2015
  • Direct Filters:
  • A Filter submenu has been added to the Web Sessions List’s context menu. Using this menu, you can quickly use attributes of the currently selected session to remove similar traffic and prevent its display in the future. For instance, I can quickly filter out all requests to a specified target host and all previously captured and future requests to that host will be hidden. The currently enabled direct filters are listed in the new Filters Gutter beneath the QuickExec box. Right-click a filter entry to remove it. Hover over the Filters label to update the numeric counter showing how many sessions were hidden by filters listed in the gutter.
  • WebSockets:
  • The long-awaited WebSockets tab is now available. Simply double-click on any WebSocket session in the Web Sessions list. The tab offers the ability to reassemble fragmented messages, and display each message’s content using a small set of Inspectors. If your WebSocket traffic contains higher-level formats (such as binary images) you can click the Inspect as Response button to send the message to the main Web Sessions list for inspection using any Fiddler Inspector.
  • AutoSave:
  • Fiddler can now automatically save SAZ archives and clear the session list on a regular schedule. Click Tools > Configure AutoSave to show the AutoSave tab
  • SAZ Clipboard:
  • Click Tools > New Session Clipboard to create a new window into which you can drag/drop sessions you’d like to keep around outside of the main Web Sessions list
  • Text Wizard:
  • Fiddler’s TextWizard has been updated with additional formats; the old radio buttons have been replaced with a drop-down list of formats.
  • Newly supported formats include conversion To Base64URL strings (often used by Java and security protocols) and To C# byte[] strings, which enable you to easily generate C# source code for a given output, like so: byte[] arrOutput = { 0xC2, 0xAE, 0xC2, 0xA9, 0xE2, 0x98, 0x85, 0x20, 0xE2, 0x98, 0x86, 0x20 };
  • HTTPS Versions:
  • Fiddler 4 has long offered a choice of HTTPS versions (defaulting to SSL3 and TLS1.0) when talking to servers, but previously using TLS1.1 and TLS1.2 required somewhat complicated configuration steps. You can now easily control what SSL and TLS versions Fiddler offers to servers using the Enabled Protocols link on the Tools -> Fiddler Options -> HTTPS Tab
  • BSON Support:
  • Fiddler’s JSON Inspector now supports display of BSON-format binary responses
  • Composer History:
  • Fiddler’s Composer tab now includes a History pane to enable you to re-issue previously composed requests easily, without having to drag and drop from the main Web Sessions list. Simply double-click on any request in the list to update the headers and body currently in the Parsed tab.
  • Image Quality Explorer:
  • The ImageView Inspector offers a new Image Quality Explorer tool that enables you to easily explore the relationship between image format/quality and file size. To invoke it, right-click an image and choose Explore Quality from the Tools submenu. The image will open in a new window. Drag the slider left to observe the impact of quality reductions on the image (shown at the top) and on the file size (shown at the bottom).
  • PNGDistill:
  • The ImageView Inspector’s Tools menu also offers the new PNGDistill tool to enable you to optimize PNG files by removing metadata and optimizing compression. While it’s easily launched by Fiddler, you can also automate the pngdistill.exe tool directly within your build and deploy scripts to ensure that performance problems are avoided before your users experience them.
  • Gallery Add-on:
  • Fiddler’s Image Gallery add-on now supports JPEG-XR and WebP images. It also supports a new slideshow mode called “picture pile” (hit the P key while in slideshow mode).
  • Performance - Dozens of performance improvements have been made around Fiddler to speed:
  • The display of large bodies of text
  • Search across sessions
  • Processing of custom columns
  • Reliability Performance:
  • On Windows Vista and later, if Fiddler hangs for any reason or encounters a crashing bug, the tool will detach the proxy and preserve as many settings as it can before restarting.
  • High DPI:
  • Various improvements were made around the Fiddler for better behavior on high-DPI systems. For instance, Fiddler’s icons now include higher-resolution versions for improved scaling, and assorted UI features now resize more appropriately on high-DPI systems. Fiddler is not yet marked as a “DPI-aware” application and, thus, will use the system’s default scaling if the screen is over 150 DPI.
  • If you’d like to disable the system’s default-scaling, you can start Fiddler with the dpiAware command-line argument.
  • Windows 10 Support:
  • Fiddler now fully supports the Windows 10 preview release.
  • Import and Export:
  • Fiddler now offers an Import Folder option to bulk-load a set of SAZ files that share a common password.
  • This update also includes numerous bugfixes to PCAP, PCAPNG, and NetMon CAP import, as well as WCAT export.

New in version (July 24th, 2015)

  • Improvements to:
  • Composer
  • WebSockets
  • AutoSave
  • Direct filters
  • SAZClipboard
  • TextWizard
  • Image-handling
  • Windows 10 support
  • ... and much more!

New in version (July 24th, 2015)

  • Improve AutoResponder
  • Improve Custom Columns
  • Improve ImageView
  • HTTP/2 detection

New in version (July 24th, 2015)

  • Zopfli and WebP support

New in version (July 24th, 2015)

  • Integrate GeoEdge

New in version (March 3rd, 2014)

  • Minor tweaks
  • Customizable icon
  • Important fix for servers with buggy socket reuse

New in version (February 27th, 2014)

  • Add PCAPNG support
  • Basic CTRL+Z undeletion
  • Improved Filters tab
  • New Art
  • Various bugfixes

New in version (February 27th, 2014)

  • Support basic CURL commands in Composer>Scratchpad
  • Add "Edit Image" to ImageView inspector
  • Improve Client Certificate handling

New in version (December 11th, 2013)

  • Add Packet Capture Import
  • Enhanced Composer
  • Enhanced AutoResponder
  • Enhanced Protocol Violation detection
  • Improved WebView
  • Add registry-fallback to EnableLoopback

New in version (October 24th, 2013)

  • Use F3/ShiftF3 to navigate Find results
  • Improved XMLView
  • Improved WebSocket support
  • Various bugfixes

New in version Beta (April 10th, 2013)

  • Enhanced QuickExec
  • Improved FiddlerHook
  • Many bugfixes

New in version Beta (March 23rd, 2013)

  • Improved column customization
  • Improved performance
  • New art
  • Many bugfixes

New in version Beta (February 9th, 2013)

  • Improved Echo service
  • Improved column customization
  • Many bugfixes

New in version (January 22nd, 2013)

  • Improved ImageView
  • Improved TextWizard
  • Many bugfixes

New in version Beta (January 16th, 2013)

  • Improved ImageView
  • Many bugfixes

New in version (December 3rd, 2012)

  • Search-by-column
  • Protocol Violation list
  • Improved Performance
  • Enhanced AutoResponder
  • New layout option (View > Layout)
  • Enhanced Fiddler Options dialog
  • Various bugfixes

New in version Beta (November 8th, 2012)

  • Search-by-column
  • Protocol Violation list
  • Performance improvements
  • UI tweaks
  • Many bugfixes

New in version (September 17th, 2012)

  • Added Encodings panel to TextWizard
  • Support Triple-click in the Scratchpad
  • Improved EnableLoopback utility
  • Update contact addresses
  • Various bugfixes

New in version (August 29th, 2012)

  • Improved Timeline
  • Enhance HTTPLint
  • Various bugfixes

New in version Beta (August 25th, 2012)

  • Improved Timeline
  • Improved about:config
  • Improved AutoResponder
  • Various bugfixes

New in version (August 17th, 2012)

  • Improved performance
  • Improved screenshot
  • Improved Composer
  • Improved QuickExec
  • Improved AutoResponder
  • Many bugfixes

New in version Beta (August 16th, 2012)

  • Improved QuickExec
  • Improved screenshot
  • Improved performance
  • Many bugfixes

New in version Beta (August 4th, 2012)

  • Improved composer
  • Improved Performance
  • Add Files > Recent menu
  • Updated sounds for script load
  • Add fiddler.Lint.HTTP feature
  • Various bugfixes

New in version Beta (July 10th, 2012)

  • Enhanced Composer including Scratchpad feature
  • Add Copy -> Response DataURI to context menu
  • Add Reissue -> Reissue From Composer to context menu
  • Add "Automatically Authenticate" rule to Rules menu
  • Various bugfixes

New in version (July 2nd, 2012)

  • Improved JSON decoder
  • Many bugfixes

New in version (June 4th, 2012)

  • Implement HTTP->FTP Gateway
  • Improved Authentication support
  • Improved request encoding support
  • Improved HAR import
  • Enhanced AutoResponder
  • Improved WebSocket support
  • Various bugfixes

New in version (June 4th, 2012)

  • Improved error handling
  • Minor new features

New in version (February 28th, 2012)

  • WebView supports all font types
  • Full TLS Extensions support
  • Improved Script Engine
  • Improved Performance
  • Various bugfixes

New in version (January 25th, 2012)

  • Enhanced Performance
  • Enhanced Inspectors
  • Important bugfixes

New in version (January 25th, 2012)

  • Major rewrite of HTTPS/WebSocket handling
  • Add File Upload to Composer (nee Request Builder)
  • Add Capture FTP checkbox
  • New overloads to BindUIColumn and AddBoundColumn to indicate column should be sorted numerically
  • Expose Original Session ID in Comments field when reloading SAZ file
  • Add HTTPS-decryption process filter
  • Add POST and quotationmark-encoding support to WCATExporter
  • In HTTPS-decryption, if we can't get the certificate, don't fail entirely, instead treat as a blind tunnel.
  • Add "Save and Open as Local &File" context menu
  • Enhanced File Exporter
  • Add FiddlerGotRequestHeaders and FiddlerGotResponseHeaders timers
  • Add HostList class for faster and more standardized handling of Hostnames.
  • Add "Run Filters now" to Filter's Action button.
  • Add more XML code description attributes
  • Enhanced AutoResponder
  • sTunnel field converted to property with correct accessors [Breaking change]
  • Various bugfixes

New in version (November 3rd, 2011)

  • Various bugfixes

New in version (October 5th, 2011)

  • Request Cookie Inspector
  • Automate firewall exemption
  • Inspect in New Window command
  • Improved Inspectors
  • Troubleshooter for Filters on the Help menu
  • Various UI improvements
  • Various bugfixes

New in version (June 23rd, 2011)

  • AutoUpgrader
  • Tweaks for Firefox 5
  • Assorted bugfixes

New in version (June 17th, 2011)

  • New features on the AutoResponder tab's context menu
  • Improved support for Apple iOS HTTPS Interception (requires add-on)
  • JSON Inspector
  • Assorted bugfixes

New in version (April 25th, 2011)

  • Add !dns [hostname] and !nslookup [hostname] to list DNS info to Log tab
  • Add !listen PORT [CERTHOSTNAME] to QuickExec
  • Add audio/video/font/silverlight/flash/HTTP-POST Session icons
  • Revamp a few toolbar icons
  • Enable +/- latency adjustments using AutoResponder
  • Add fiddler.ui.inspectors.request.alwaysuse and fiddler.ui.inspectors.response.alwaysuse preferences
  • Changed "Remove Un-Marked" to ignore breakpointed sessions
  • Added fiddler.ui.CtrlX.KeepMarked and fiddler.ui.CtrlX.PromptIfMoreThan # (to replace CONFIG.iPromptBeforeClearAll)
  • Add Screenshot toolbar command, including delay option
  • Delay-Create FiddlerScript file behind pref "fiddler.script.delaycreate" defaults to true
  • Add IE10 User-Agent to default rules
  • Add AlwaysFresh option to Performance menu
  • Add fiddler.requestbuilder.followredirects.max preference
  • Add actInvertSelectedSessions() with hotkey of CTRL+I
  • about:network is now a synonym for about:connectoids
  • Add support for SELECT @REQUEST.HEADER VALUE, use * to test for existence or "\*" to match on a literal star.
  • Various bugfixes

New in version (April 14th, 2011)

  • Improved AutoResponder with latency and per-rule editor
  • Add support for QuickLinkMenu and QuickLinkItem
  • Various bugfixes

New in version (April 4th, 2011)

  • Allow save/load of session content to FARX file, using compression if needed
  • Added "Open URL" to AutoResponder rules menu
  • Add "11" to Options > Font Size dropdown; enable CTRL+Plus, CTRL+Minus, CTRL+0
  • Set the mouse cursor for the interactable panels on the Status Bar
  • Support sequential requests via # token in RequestBuilder
  • Don't trim a User-Marked/Commented session
  • Add "Remove Un-Marked" to toolbar menu
  • Update _replaceVirtualHostnames to update request line for CONNECT tunnels
  • Fixed the directly-specified Proxy script handling code; added preference
  • Fix AutoResponder's Connect+AlternateURL scenario
  • AutoResponder now emits detailed 404 error if session has a process ID or was generated by Fiddler
  • Update installer for Win7+ You must use "Turn Windows features on or off" in the Control Panel to install or configure Microsoft .NET Framework 2.0 SP2 for Windows 7+

New in version (April 4th, 2011)

  • Improved Performance
  • Improved AutoResponder
  • Improved support for Windows Phone emulator
  • Edit preferences with about:config
  • Various small improvements
  • Lots of bugfixes

New in version (February 11th, 2011)

  • Improved support for Windows Phone emulator
  • Editing preferences enabled in about:config

New in version (July 26th, 2010)

  • Various small improvements
  • Lots of bugfixes

New in version (June 28th, 2010)

  • Import/Export feature
  • Tons of bugfixes

New in version (February 1st, 2010)

  • Added -viewer switch for new "view only" mode
  • Improved Filters tab
  • Improved Request Builder
  • Improved FiddlerHook for Firefox
  • Various bugfixes

New in version (February 1st, 2010)

  • 64-bit support
  • Added Tools > HOSTS
  • Improved inspectors
  • Improved performance
  • Various bugfixes

New in version (August 6th, 2009)

  • Improved Text Encoder/Decoder
  • Improved performance
  • Improved FiddlerHook
  • Various bugfixes

New in version (June 16th, 2009)

  • New Fiddler toolbar
  • Improved Timeline
  • Performance and fidelity improvements
  • Include WebView inspector by default
  • Various bugfixes

New in version (April 17th, 2009)

  • Added FiddlerHook Firefox Extension
  • Hook all connections by default
  • Improved TextWizard
  • Improved default behavior of Find dialog
  • Allow drag/drop of files to AutoResponder to create new rules
  • Assorted bugfixes

New in version (June 20th, 2008)

  • Improved Fiddler Options dialog
  • ProcessID column added to Session List
  • Process Filter added to Filters tab
  • Improved Upstream Gateway support
  • Improved Performance
  • AutoStream Video option
  • Various bug fixes

New in version (November 15th, 2007)

  • Improved APIs for automation
  • Improved inspectors
  • Improved SimpleFilter tab
  • Improved HTTP compression efficiency
  • Improved international support
  • Improved TextWizard
  • Many bugfixes

New in version (October 17th, 2007)

  • New context menu Select Parent/Children/Duplicates (or hit D,C,P)
  • SimpleFilters tab now included by default
  • Improved Session Archive File format with timestamps
  • Improved streaming mode
  • Improved inspectors
  • Improved performance
  • Improved extensibility
  • Improved international support
  • Improved search box
  • Improved Header editor including header templates
  • Many bugfixes

New in version Beta (August 31st, 2007)

  • Improved Inspectors (WebForms/Cookies/Hex/Etc)
  • Improved Save As WebTest
  • Support for HTTPS connection reuse and upstream HTTPS gateways
  • More explicit http errors on malformed response.
  • Various bugfixes

New in version 1.1.6 (May 10th, 2006)

  • Introduced support for upstream proxy autodetection and configuration scripts (http/https delivered scripts only)
  • Enhanced Find Sessions feature with new options
  • Added "Clone response" to session context menu
  • Fixed upstream NTLM/Negotiate proxy support
  • When DebugSpew is on, both requests and responses dumped to debug console in hex format
  • Change default for CaptureCONNECT to True
  • Added FiddlerObject.UI.actReloadInspectors() added to simplify inspector development
  • Fixed Save as WebTest in various ways
  • Allow userscript to override the hostname used to determine upstream IP, without changing the HTTP headers. This enables HOSTS-file type scenarios where a request should be sent to an alternative server. e.g. in your OnBeforeRequest() handler, put code like: if ("") { oSession["x-overrideHost"] = "" } Obviously, this doesn't work if you have an upstream proxy, and you have to just tweak directly for those cases.
  • Performance and Robustness improvements