StegSolve Alternative — AperiSolve, StegOnline, and Browser Tools Compared

StegSolve.jar stopped working reliably on modern systems years ago, and the CTF community has been piecing together alternatives ever since. Three tools are commonly recommended: AperiSolve, StegOnline (georgeom.net), and StegSolve Online. This guide compares them feature-by-feature so you can choose the right tool for your challenge.

→ Try StegSolve Online — free, browser-based, no upload

The Three Main Alternatives#

AperiSolve (aperisolve.com)#

AperiSolve is a server-side analysis service. You upload an image and it runs a suite of real tools: zsteg, steghide, outguess, binwalk, foremost, and others — the same command-line tools a security researcher would use manually.

Strengths:

• Runs actual zsteg and steghide (tools that require C/Ruby installs locally)
• Covers more attack surface in one click (file extraction, binwalk, exiftool)
• Good for quick automated scanning with real tools

Weaknesses:

• Your image is uploaded to a remote server — a concern for CTF environments with NDAs, or for sensitive images
• Server-side: depends on network connectivity and server availability
• Can be slow under load
• No visual bit plane navigation — you can't look at individual planes interactively
• No image combiner
• No GIF frame browser
• No brute-force extraction scanner

StegOnline (georgeom.net)#

StegOnline is the closest visual equivalent to the original StegSolve: browser-based bit plane viewer with data extraction. It runs client-side, so no files are uploaded.

Strengths:

• Client-side: no file upload
• Good bit plane viewer (all 32 planes, including 8-bit view)
• Basic LSB extraction

Weaknesses:

• No chi-square analysis — can't detect whether steganography is present
• No brute-force scanner
• No PNG chunk analysis
• No GIF frame browser
• No image combiner
• No flag auto-detection
• No stereogram solver
• Appears unmaintained (last updates unclear)

StegSolve Online (stegotoolkit.com)#

StegSolve Online is a browser-native reimplementation of the original StegSolve.jar with significant additions. It runs entirely client-side — no files are uploaded.

Strengths:

• Every original StegSolve feature (28 bit planes, extraction, combiner, frames, stereogram)
• Grid view of all 28 planes simultaneously — the single biggest UX improvement over all competitors
• Chi-square LSB detection per channel
• Brute-force channel combinator (200+ configurations, ranked by readability)
• Auto-scan on upload: chi-square, entropy, flag patterns, PNG chunks, extra bytes
• Auto flag detection for all common CTF formats
• Auto-decode (base64, hex, ROT13)
• PNG chunk analysis (tEXt, zTXt, non-standard chunks)
• Pixel zoom up to 16× (nearest-neighbour, no blur)
• CLI equivalents for every extraction config
• Session restore after page reload
• CTF checklist for writeups

Weaknesses:

• Does not run actual steghide, outguess, or binwalk (these require server-side execution)
• No file format extraction (binwalk-style) — focuses on pixel-level and chunk analysis

Feature Comparison#

| Feature | AperiSolve | StegOnline | StegSolve Online | |---|---|---|---| | Bit planes (28) | ✅ (via zsteg) | ✅ (visual) | ✅ (visual, grid + single) | | Grid view (all planes) | ❌ | ❌ | ✅ | | Data extraction | via zsteg | ✅ basic | ✅ full controls | | Image combiner (XOR/AND) | ❌ | ❌ | ✅ | | GIF frame browser | ❌ | ❌ | ✅ | | Stereogram solver | ❌ | ❌ | ✅ | | Chi-square analysis | ✅ (via zsteg) | ❌ | ✅ (per channel) | | Brute-force scanner | ❌ | ❌ | ✅ 200+ combos | | Auto flag detection | ✅ (via zsteg) | ❌ | ✅ | | PNG chunk analysis | ✅ (via binwalk) | ❌ | ✅ | | Actual steghide/outguess | ✅ | ❌ | ❌ | | Actual zsteg (Ruby) | ✅ | ❌ | ❌ | | File extraction (binwalk) | ✅ | ❌ | ❌ | | No file upload (privacy) | ❌ Uploads to server | ✅ | ✅ | | Works offline | ❌ | ❌ | ✅ (PWA) | | Pixel zoom | ❌ | ❌ | ✅ 1×–16× |

When to Use Each Tool#

Use AperiSolve when:

• You need actual steghide or outguess to extract a payload (these need real binaries)
• You want a quick all-in-one automated scan and privacy is not a concern
• The challenge involves file-level steganography (data hidden with binwalk-detectable techniques)

Use StegSolve Online when:

• You need visual bit plane analysis — looking at individual planes to spot patterns
• You need data extraction with custom channel/bit/order settings
• You're combining two images (XOR challenges)
• You're browsing GIF frames
• Privacy matters (your file never leaves the device)
• You're on a restricted network without upload access
• You want the brute-force scanner to find the right channel combination automatically

Use StegOnline when:

• You need basic bit plane viewing and StegSolve Online is unavailable

The Recommended CTF Workflow#

For most image challenges, the fastest workflow combines the tools:

1. Upload to StegSolve Online first — get the auto-scan result. If chi-square is elevated or the auto-scan found something, use the brute-force tab to extract. Grid view lets you spot suspicious planes in seconds.

2. If that finds nothing: upload to AperiSolve for zsteg -a (exhaustive scan) and steghide with empty password. This catches techniques like steghide injection that pixel-level analysis won't find.

3. For standard LSB CTF challenges: StegSolve Online resolves the majority in under 30 seconds — auto-scan + one click on the flagged channel.

Most CTF image challenges are solved at step 1. AperiSolve fills the gap for steghide and outguess challenges.

Privacy Note#

AperiSolve explicitly requires file upload. The site is operated by a community member and is generally trusted in the CTF community, but be aware that your challenge images are transmitted to a remote server.

StegSolve Online and StegOnline both process images locally. For any challenge where the image itself might contain sensitive data (red team exercises, OSCP labs, professional engagements), client-side tools are the appropriate choice.

→ Open StegSolve Online — analyze images without uploading

For broader statistical steganography detection across multiple test methods, the Steganography Analyzer runs chi-square, RS Analysis, Sample Pairs, and Primary Sets tests.