100% Client-Side Privacy Tool
PST & OST File Structure Inspector
Analyze your Outlook `.pst` or `.ost` file locally in your browser. Check format type (ANSI vs 64-bit Unicode), size limits, and corruption markers — 100% offline, zero server uploads!
Select or Drag & Drop Outlook File (.pst / .ost)
Select any PST or OST file from your hard drive to inspect header bytes. Your file never leaves your computer.
Browse File on Computer Header Inspection Complete
sample_mailbox.pst
UNICODE 64-BIT (SAFE)
File Size 4.85 GB
Structure Type Unicode 64-bit
Size Risk Low (Under 50GB)
Outlook 2003–2026 Compatible: ✓ 100% Compatible
macOS Native Conversion Ready: ✓ Native Universal Binary Ready
Microsoft Outlook MAPI Needed: 🛡️ Zero (Standalone Engine)
Recommended Action
Ready to Convert This File?
Convert to Gmail, Office 365, MBOX, or PDF with Prism Standalone Engine.
Flagship Converter
PST Converter Tool →
25 GB/hr standalone 64-bit engine with 17 export formats.
macOS SolutionHow to Open PST on Mac Outlook →
Native Apple Silicon M1-M4 conversion guide.
Cloud MigrationImport OST to Office 365 →
Direct OAuth 2.0 ingestion without Exchange Server.
Benchmark HubCompare vs Legacy Tools →
$29 1-Year license vs $99–$299 annual renewals.
100% Browser Local Processing Privacy Guarantee:
This inspection tool uses JavaScript HTML5 FileReader API to read the first 512 bytes of your file directly in memory inside your web browser. No data or file contents are uploaded to any server.