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Best Debuggers in 2026

When you need to understand a program’s behavior or track down an error, a debugger lets you inspect execution and respond to breakpoints. Compared on supported languages and target platforms, these tools can be assessed against the environments you work in. Conditional and exception breakpoints, remote debugging, core dump debugging, and time-travel debugging offer further points of comparison. Free-plan availability and the paid-from price add cost context. LLDB, IDA Pro, and FlowStorm are among the entries shown. Think about the kind of issue you need to trace and which debugging techniques are relevant before comparing the available options.

  1. 1

    Black Magic Debug

    Free plan LinuxMacWindows

    Choose Black Magic Debug if you need a free JTAG/SWD debugger with automatic target detection and control over your embedded development setup.

    7.6 Free plan Visit site
  2. 2

    FlowStorm

    Free plan LinuxMacSelf-hosted+1

    FlowStorm combines execution recording with stepping, inspection, visualizations, and thread-event timelines for Clojure and ClojureScript.

    7.5 Free plan Visit site
  3. 3

    LLDB

    Free plan AndroidiPhoneLinux+2

    LLDB combines debugger tools with APIs and editor integrations, and is the default debugger in Xcode on macOS.

    7.4 Free plan Visit site
  4. 4

    OpenOCD

    Free plan LinuxMacSelf-hosted+1

    OpenOCD provides debugging, programming, and boundary-scan tools across a range of listed targets and interfaces.

    7.4 Free plan Visit site
  5. 5

    Delve

    Free plan APILinuxMac+2

    Delve offers broad debugging commands and editor integrations for Go, with a free MIT-licensed project.

    7.3 Free plan Visit site
  6. 6

    dnSpyEx

    Free plan LinuxWindows

    dnSpyEx combines debugging, decompilation, editing, and assembly analysis at no cost. Its dynamic-method limitation and Wine-based Linux use are important constraints.

    7.3 Free plan Visit site
  7. 7

    GDB

    Free plan LinuxMacWindows

    GDB covers program inspection across multiple operating systems, languages, and target types. Some capabilities depend on platform support or a Python-enabled build.

    7.3 Free plan Visit site
  8. 8

    IDA Pro

    Free plan LinuxMacWindows

    IDA Pro combines disassembly, decompilation, debugging and automation tools, with team and private knowledge-base options.

    7.3 From $1,099/yr Visit site
  9. 9

    PonyDebugger

    Free plan iPhoneMacSelf-hosted+1

    PonyDebugger offers Chrome Developer Tools views for native iOS app debugging, including network and interface inspection.

    7.3 Free plan Visit site
  10. 10

    pyOCD

    Free plan APILinuxMac+2

    pyOCD combines GDB debugging, flash programming, and Python-based device control for Arm Cortex targets.

    7.3 Free plan Visit site
  11. 11

    Perl Debugger

    Free plan LinuxMacWindows

    Choose Perl Debugger if you need a free, Perl-specific way to inspect execution, set breakpoints, and examine values. It is included with Perl rather than installed as a separate debugger.

    7.2 Free plan Visit site
  12. 12

    CUDA-GDB

    Free plan LinuxSelf-hosted

    Choose CUDA-GDB if you are working on CUDA applications in Linux or QNX and need to debug CPU and GPU code together.

    7.1 Open source Visit site
  13. 13

    FLEX

    Free plan iPhone

    FLEX provides in-app inspection for a wide range of iOS development tasks, without a remote debugging connection.

    7.1 Free plan Visit site
  14. 14

    Redbird

    Free plan APILinuxSelf-hosted

    Pick Redbird if you want a no-cost, self-hosted Node reverse proxy with flexible routing, WebSocket support, and automatic certificate generation.

    7.1 Free plan Visit site
  15. 15

    RenderDoc

    Free plan AndroidLinuxWindows

    RenderDoc offers frame-capture debugging across several graphics APIs, with platform-specific limits to consider.

    7.1 Free plan Visit site
  16. 16

    OllyDbg

    Free plan Windows

    Choose OllyDbg if you need a free Windows debugger for binary analysis and value its breakpoint, tracing, patching, and plugin options.

    6.9 Free plan Visit site
  17. 17

    Xdebug

    Free plan LinuxMacSelf-hosted+2

    Xdebug combines step debugging with tracing, profiling, and code coverage for PHP projects.

    6.9 Free plan · paid from £200/yr Visit site
  18. 18

    Ruby debug

    Free plan LinuxSelf-hosted

    Choose Ruby debug if you work with Ruby MRI 2.7 or later and want a debugger with breakpoints, remote attachment, and backward replay.

    6.8 Open source Visit site
  19. 19

    unittest

    Free plan LinuxMacWindows

    unittest provides test organization, command-line execution, discovery, and mock support as part of Python’s standard library.

    6.8 Free plan Visit site
  20. 20

    x64dbg

    Free plan Windows

    Choose x64dbg if you need a free Windows debugger for reverse engineering or malware analysis, with support for both x64 and x32 targets.

    6.5 Free plan Visit site
  21. 21

    UDB

    Free trial ExtensionLinux

    UDB combines recording-based replay with conventional debugging controls for Linux C and C++ work.

    5.7 Pricing on request Visit site
  22. 22

    Erlang Debugger

    Paid LinuxMacWindows

    Choose Erlang Debugger when you need a graphical way to test Erlang programs, inspect processes, or control execution with breakpoints.

    5.5 Open source Visit site
  23. 23

    SEGGER Ozone

    Paid LinuxMacWindows

    Ozone combines source debugging, performance analysis, and automation for embedded development across three desktop operating systems.

    5.4 Visit site
  24. 24

    WinDbg

    Free plan Windows

    WinDbg provides a broad set of debugging and dump-analysis capabilities at no listed cost. It is focused on Windows use while also handling Linux crash dumps.

    5.4 Free plan Visit site
  25. 25

    TRACE32

    Paid LinuxMacWindows

    TRACE32 provides broad embedded processor debugging and trace capabilities, with configurable hardware and license dependencies.

    5.3 Pricing on request Visit site

#1Places #1, #2, #3, #4, #5 on this list can be bought by the makers of the software on it. See the price

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