Bytecode Viewer — authorized Java & Android bytecode suite

Last updated: · By the BinBench editorial team · Stars and releases checked via the GitHub API
For legal, authorized and educational use only. Only analyze software you own or have written permission to examine.
Quick answer

Bytecode Viewer (Konloch/bytecode-viewer) is a Java/Android bytecode RE suite. Release v2.13.2 (2026-01-01 UTC; Windows APK fixes re-cut 2026-01-06 UTC) was the latest Release object on 2026-10-24. License is GPL-3.0. Analyze only JARs/APKs you are authorized to examine.

On this page

Snapshot

FieldValue
LicenseGPL-3.0
Latest checkedv2.13.2 (2026-01-01 UTC; re-release 2026-01-06)
JobMulti-view JAR/APK decompiler/editor suite
Stars (order of magnitude)~15.7k on GitHub (counts change daily)
Peersjadx, dnSpyEx/ILSpy for .NET

Allowed framing

  • Inspecting your Java builds and lab APKs in a GUI.
  • Comparing decompiler panes for classroom demos.
  • Triage of ticketed JAR samples on disposable hosts.

Scope we will not cover

  • No crackme “auto-solve commercial software” framing.
  • No license-check / DRM bypass recipes.
  • No hosting of proprietary JARs on BinBench.

Beginner path (authorized only)

  1. Prefer a disposable lab VM; snapshot before loading unknown samples.
  2. Download the official Bytecode-Viewer-2.13.2.jar from Konloch/bytecode-viewer Releases.
  3. Start with a tiny JAR you compiled; keep the exact BCV version in notes.
  4. If you need the older CLI, follow upstream guidance to pin v2.12 rather than inventing flags.
  5. Pair Android-heavy work with jadx notes.
Which to pick
  • Use Bytecode Viewer for a GUI multi-decompiler look at authorized JAR/APK targets.
  • Prefer jadx for many Android-first decompilation workflows.
  • Stay inside authorized-use framing.

For legal, authorized and educational use only.

FAQ

What is Bytecode Viewer?

Bytecode Viewer (BCV) is a Java reverse-engineering suite for JAR and Android APK targets, bundling decompiler/editor views so you can inspect bytecode you are authorized to examine.

Which version is cited?

v2.13.2 published 2026-01-01 UTC (re-released 2026-01-06 UTC for Windows APK/Dex2Jar fixes) on Konloch/bytecode-viewer Releases. Upstream labels it in-development; CLI was nonfunctional during a rewrite at publish time — use v2.12 when you need the older CLI per release notes.

What license applies?

GNU GPL v3; GitHub reports GPL-3.0 (checked 2026-10-24).

jadx or Bytecode Viewer?

Prefer jadx for Android-focused Java decompilation workflows. Prefer Bytecode Viewer when you want its multi-decompiler JAR/APK GUI suite on authorized packages.

Does this teach cracking commercial Java apps?

No. Decompile only packages you own or may examine under authorization.

Sources