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File Type Checker

Smart File Type Verifier

Detect the real type of your files by analyzing byte signatures, not relying on extensions. Uses Magika to identify hidden, corrupted or modified files with professional precision.

✓ Advanced byte signatures ✓ MD5 / SHA256 Hashes ✓ ZIP, EXIF and metadata ✓ Polyglot detector ✓ PDF/Excel Reports ✓ Try it without an account
Also on Android Get it on Google Play

Drag files here

or click to select

ZIP PDF IMG DOCX MP3 +100 more

Maximum 10MB without account · View plans

Need more capacity? View Pro plan →

New Hash Reputation (MalwareBazaar) · Polyglot Detector · Encrypted File Classifier See all features →
300MB Maximum size (Pro)
+100 Supported formats
100% Private
24/7 Available

Why ARevo Scanner?

Precise Detection

Deep byte signature analysis, does not depend on extensions

Instant

Results in seconds, no downloads or software installation

Private and Secure

Your files are analysed on our server and discarded when done: they are not stored

Detailed Reports

Metadata, EXIF and compressed file analysis

Compressed file analysis is included in the Pro plan

See all features →

How does detection work?

Analysis by byte signature

Every file format has a characteristic byte sequence at the beginning (magic bytes). ARevo Scanner reads these bytes directly and compares them against a signature database to identify the real type, completely ignoring the name or extension.

  • PDF always starts with %PDF-
  • ZIP with PK\x03\x04
  • PNG con \x89PNG\r\n

Byte pattern analysis based on the Magika model, open-source software published by Google. google/magika

{
  "filename": "documento.exe",
  "declared_ext": "exe",
  "real_type": "application/pdf",
  "confidence": 99,
  "is_correct": false,
  "magic_bytes": "25 50 44 46"
}

PHP finfo_file()

The native PHP finfo_file() function queries the OS MIME type database to determine the file type. Combined with our signature analysis, it offers double-layer detection.

PHP finfo_file() docs · MIME registry: IANA Media Types

Extension Real type Risk
.jpg → .exe application/x-msdownload High
.pdf → .js application/javascript High
.png → .png image/png OK
.docx → .zip application/zip Medium

Real-time process

The analysis occurs in milliseconds: the file travels to the server via FormData, PHP reads the first bytes, runs finfo_file(), calculates hashes and returns the full result in JSON.

1Upload via FormData
→
2Magic bytes reading
→
3finfo + signatures
→
4JSON response

Plans and Limits

Need more detail? See the full feature comparison.

No Login

Free
  • Up to 10 MB per file
  • 1 simultaneous analysis
  • Download JSON
MOST POPULAR

Pro

€5/Month

Professional analysis without limits

  • Up to 300 MB per file
  • 20+ simultaneous analyses
  • JSON + CSV + PDF + Excel
  • Advanced reports

No commitment · Cancel anytime

Free

$0
  • Up to 50 MB per file
  • 5 simultaneous analyses
  • History (30 days)
Create Free Account

Detailed comparison

Feature No Login Free Pro
Max file size 10 MB 50 MB 300 MB
Simultaneous files 1 5 20+
Export formats JSON JSON + CSV JSON + CSV + PDF + Excel
MD5 / SHA256 Hashes ✗ ✓ ✓
Entropy classifier ✗ ✓ ✓
Metadata (EXIF, PDF, DOCX) ✗ ✗ ✓
Compressed file analysis ✗ ✗ ✓
Polyglot detector ✗ ✗ ✓
VirusTotal link ✗ ✗ ✓
Hash reputation (MalwareBazaar · ThreatFox) 3/day 20/day 200/day
History ✗ 30 days Unlimited
PDF / Excel reports ✗ ✗ ✓
Support ✗ Email Priority

Preguntas frecuentes

Are my files uploaded to the server?
Yes, files are sent to the server so PHP can read their bytes. However, they are never saved to disk: they are processed in memory and discarded immediately after analysis.
Is it safe to analyze malware or suspicious files?
finfo_file() is the native PHP function that queries the system MIME database. On top of it, ARevo Scanner applies the Magika detection model, open-source software published by Google: it reads the first bytes of the file and compares them against a signature database, offering greater precision than finfo in ambiguous cases.
What is a polyglot file and why is it dangerous?
A polyglot file is simultaneously valid as two or more different formats. For example, a file that is both a JPEG image and an executable PHP script. They are dangerous because they can bypass security filters that only check the extension or superficial MIME type.
→ CWE-434: Unrestricted File Upload (MITRE/NIST)
What happens if the format is not recognized?
The analyzer returns the type application/octet-stream (generic binary) along with the entropy level of the file. Very high entropy may indicate it is encrypted or compressed with a non-standard algorithm.
Can I analyze multiple files at once?
It depends on your plan: No Login allows 1 file per analysis, Free Plan up to 5 simultaneously, and Pro Plan up to 20+. You can select multiple files by dragging them to the upload zone.
→ Compare all plans
How do I cancel the Pro plan?
You can cancel at any time from your dashboard, in the "Subscription" section. There is no minimum commitment. If you cancel, you keep Pro access until the end of the billing period.
Is it safe to upload confidential files?
Files are processed in memory and discarded immediately. They are not saved to disk or shared with third parties. For maximum privacy, avoid uploading files with unencrypted sensitive data.
What file types can it analyze?
ARevo Scanner detects over 100 formats: images (JPEG, PNG, WebP, HEIC), documents (PDF, DOCX, XLSX), compressed files (ZIP, RAR, 7z), executables (EXE, ELF, Mach-O), scripts, audio, video and generic binaries.
Does ARevo Scanner detect malware?
No, it is not an antivirus. It checks whether the file really is what its extension says. It also compares the file's SHA256 hash with MalwareBazaar and ThreatFox, databases of known malware: if it matches, we tell you. If there is no match, that does not guarantee the file is safe, only that it is not a known sample. Only the hash is sent, never the file.