Fiddler Classic

Release History

Fiddler v2.x

January 20, 2014

Fiddler v2.x

The latest Beta change log.

Note: Fiddler 4.x and Fiddler 2.x are essentially the same code; Fiddler4 is compiled targeting .NET4 while Fiddler 2.x targets .NET2. Fiddler 2.x is no longer updated.
5.0.20192.25091 [06/04/2019]
 Security fix CVE-2019-12097
 Update all copyright strings to Progress Software EAD
 Various bugfixes and improvements
5.0.20182.28034 [06/27/2018]
 Publish Fiddler Chocolatey package
 Report the usage of all features with the analytics
 Update all copyright strings to Telerik EAD
 Various bugfixes and improvements

5.0.20181.14850 [03/20/2018]
 Fixed broken UI on high resolution/dpi monitors
 Changed x86 target architecture to AnyCPU
5.0.20181.13826 [12/01/2017]
 Improvements in Fiddler Orchestra
 Various bugfixes and improvements

5.0.20173.50948 [12/15/2017]
 Android Client Added for Fiddler Orchestra
 Non-Fiddler generated certificate can be used in Fiddler Orchestra .NET Core Client reverse HTTPS proxy
5.0.20173.49666 [12/01/2017]
 Fiddler now built AnyCPU and not x86

4.6.20172.31233 [07/20/2017]

 Fiddler installs per user now. Multiple installations can coexist on the same machine
 Minor fixes and improvements.

4.6.20171.26113 [06/13/2017]
 Updated EULA
 Various fixes and improvements

4.6.20171.14978 [03/22/2017]
 Fixed "Ignore server certificate errors(unsafe)" checkbox being checked by default.
 Fixed ServerChatter NullReference exception.
 Transformed the PDBs to MDBs for Linux build. 
 Implemented DescribeConnectionSecurity for MONO. 
 Fixed HTTPS for Mono 4.8.0. 

4.6.20171.9220 [02/09/2017]
 Minor fixes in Fiddler and Fiddler Script Editor C# functionality
 Improved .NET framework recognition in installer
 Fiddler for .NET2 start up bug fixed

4.6.20171.7553 [01/27/2017]
 Added C# scripting
 Integrated Syntax-Highlighting Add-Ons (Fiddler Script Editor) in Fiddler 
 Fixed exceptions on finding resources
 Auto update improvements [12/09/2016]
 Added Brotli decompression support
 Fixed spamming of system debug console on Telerik Analytics upload failure 
 Fixed uninstall does not remove all files   
 Changed appconfig to make Fiddler run on CLR v4 if available at the client 

Version - Released 10/25/2016

 SampleRules.js now has Windows style line endings and can be conveniently edited in notepad
 Fixed installer issue in Windows 10
 Improved update

Version - Released 07/26/2016
 Fixed sha1/sha256 dual sign of installer and executables
 Added PDB files for better exception reports
 APITest tab visible by default
Version Released 07/11/2016
 Fixed updater error message on successful update
 Added signing to all Telerik Fiddelr executables
 Improved emergency update session tool-tip behaviour

Version - Released 12/30/2015

Fiddler continues to improve. See what's new in this blog post.

Version - Released 03/20/2015

This is the biggest update in years-- see what's new:

Improvements to:
Direct filters
Windows 10 support
... and much more!

Version - Released 12/18/2014

Add Tools > Configure AutoSave
Improve Composer
Improve AutoResponder
Improve ImageView
Improved Performance
Various bugfixes

Version - Released 10/27/2014

Improve AutoResponder
Improve Custom Columns
Improve ImageView
HTTP/2 detection

Version - Released 7/8/2014
Zopfli and WebP support

Version - Released 4/23/2014
Various bugfixes

Version - Released 3/31/2014
Integrate GeoEdge

Version - Released 02/20/2014

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

Version - Released 01/02/2014

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

Version - Released 01/02/2014

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

Version - Released 12/10/2013

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

Version - Released 10/23/2013

Use F3/ShiftF3 to navigate Find results
 Improve XMLView
 Improve WebSocket support

Version - Released 1/21/2013

Improved ImageView
Improved TextWizard

Version - Released 11/30/2012

Protocol Violation list
Improved Performance
Enhanced AutoResponder
New layout option (View > Layout)
Enhanced Fiddler Options dialog 

Version - Released 9/15/2012

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

Version - Released 8/28/2012

Improved Timeline
Improved AutoResponder
Enhanced HTTPLint

Version - Released 8/16/2012

Improved performance
Improved screenshot
Improved Composer
Improved QuickExec
Improved AutoResponder

Version - Released 6/23/2012

Improved JSON decoder

Version - Released 6/3/2012

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

Version - Released 3/30/2012

Improved error handling
Minor new features

Version - Released 2/27/2012

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

Version - Released 1/23/2012

Enhanced Performance
Enhanced Inspectors
Important bugfixes

Version - Released 10/20/11

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]

Version - Released 10/20/11

Various bugfixes

Version - Released 10/4/11

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

Version - Released 6/22/11

Tweaks for Firefox 5

Version - Released 6/16/11

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

Version - Released 4/24/11

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

Version - Released 4/12/11

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

Version - Released 4/3/11

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+

Version - Released 2/12/11

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

Version - Released 10/1/10

Various small improvements
Lots of bugfixes

Version - Released 7/23/10

Various small improvements
Lots of bugfixes

Version - Released 6/24/10

Import/Export feature
Tons of bugfixes

Version - Released 1/28/10

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

Version - Released 11/9/09

64-bit support
Added Tools > HOSTS
Improved inspectors
Improved performance

Version - Released 8/4/09

Improved Text Encoder/Decoder
Improved performance
Improved FiddlerHook

Version - Released 4/18/09

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

Version - Released 3/31/09

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

Version - Released 12/17/08

Assorted bugfixes

Version - Released 12/1/08

"Monitor all connections" option
Support for commenting on sessions
Enhanced QuickExec
Added "Decode compressed content" option to Find Sessions
UI columns now extensible via BindUIColumn or AddBoundColumn APIs 
Unlocking of sessions (see context menu) for editing after completion 

Version - Released 11/11/08

Improved Autoresponder
Improved user-agent spoofing
Improved performance
Support for BZip2 compression

Version - Released 9/16/08

Lightweight process filter in status bar
New "quiet mode" feature (-quiet on command line)
Improved request builder

Version - Released 8/5/08

Improved AutoResponder, including playback from .SAZ file
Support http://ipv4.fiddler and http://ipv6.fiddler 
Added > < and = operators to QuickExec
Improved HTTPS Certificate Error handling
Filter rules automatically reload
Minor performance improvements

Version - Released 5/3/08

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

Version - Released 3/10/08.

Improved HTTPS support
Improved installer compatibility with Vista
Fixed Win2k bug preventing use of Fiddler

Version - Released 3/1/08.

Improved Inspectors and Extensions
Map requests back to process ID (oSession.oFlags["x-ProcessInfo"])
Added Response Templates
Improved AutoResponder (RegEx support)

Version - Released 1/28/08.

SmartScroll of Session List
Enhanced Timers
Many bugfixes

Version - Released 11/12/07.

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

Version - Released 9/15/07.

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

Version - Released 7/6/07.

General Improvements
Introduced Client certificate support
Improved performance
Numerous bugfixes

Extensibility Improvements
Added FiddlerApplication.UI
Added CodeDescriptions to Fiddler.CONFIG, updated visibility of some functions

Version - Released 6/28/07.

Extensibility Improvements
Added IFiddlerExtension, IAutoTamper, and IHandleExecAction interfaces
List loaded Fiddler Extensions in Options dialog
Added FiddlerApplication object
Added oSession["log-drop-request-body"] and oSession["log-drop-response-body"]
Added bBufferResponse to Session object
Added UriScheme property to HTTPRequestHeaders & Parse it from request headers

Improved HTTPS/Networking Support
New IPv6 options
Defaulted HTTPS-decryption to false
Added "Learn more" link for HTTPS support
Reloading secure traffic correctly reloads protocol
Added "Enable IPv6" to Tools > Fiddler Options
Added CaptureFTP Registry value and CONFIG.bCaptureFTP 
Added CLR Version and Windows Version to Exception Reporting

Version - Released 5/25/07.

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

Version - Released 4/12/07.

Improved WebTest Export code
Improved "Caching" inspector
Introduced /noattach command-line option
Added Session.ResetSessionCounter();
Rudimentary Session.Timer introduced
Added WinINETCache information to session Properties dialog

Version - Released 3/11/07.

Fixed Image inspector to size correctly 
Improved AutoFiddler support 
Introduced SAZ file extension for ZipArchives 
Fixed race condition in root certificate generation 
Improved IPv6 support

Version - Released 2/14/07.

Fixed "Simulate modem speeds"  feature (request-trickle-delay, response-trickle-delay) for HTTPS traffic

Version - Released 2/13/07.

Version - Released 1/29/07.

Completed AutoResponder tab
Minor new features, bugfixes.

Version - Released 1/16/07.

Version 2.0.8 - Released 11/25/06.

First public alpha

Version 2.0.7 - Released 11/10/06.

Version 2.0.4- Released 8/23/06.

Version 2.0.3 - Released 8/20/06.

Fixed hang when notifying of new version
Smooth scrolling of Session List 
Tools | Fiddler Option to disable HTTPS decryption 
Assorted bug fixes; code forked from Fiddler v1.2.0.7

Version 2.0.2 - Released 8/17/06.

Exception handling no longer crashes process
Fixed up CertMaker to set correct EKU
Added IgnoreServerCertErrors option
Disabled Server Cert revocation check

Version 2.0.1 - Released 8/16/06.

Updated release with significant improvements to stability.
Harmless (in Fiddler 1.2) exceptions now result in process termination if you acknowledge the Watson dialog (Apparently, an improvement in .NET 2.0. Later builds use a workaround).

Save the following as C:\program files\fiddler\fiddler.exe.config
<legacyUnhandledExceptionPolicy enabled="1" /> 

Version 2.0 - Released 8/9/06.

Initial Release

Fiddler Classic

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