Pick a diagnostic station.
Each tool runs locally in your browser. Some scan only structure; see each tool's limits.
Showing all 34 diagnostic tools.
Inspection
Universal File Health Check
Diagnose file format, header, size, and basic structural problems in your browser.
Identify a File by Its Signature
Discover the actual file format by reading its magic bytes, not just its extension.
File Extension Mismatch Checker
Check whether a file extension agrees with its detected internal format.
Free File Header Hex Viewer
Inspect the first bytes of any file as hexadecimal and readable ASCII.
Checksums
SHA-256 File Checksum
Calculate a SHA-256 fingerprint locally to verify file integrity.
SHA-512 File Checksum
Calculate the SHA-512 hash of your file privately in the browser.
CRC32 File Checksum
Calculate a CRC32 checksum to compare file copies and transfers.
Compare Two Files for Identical Content
Determine whether two files contain identical bytes using SHA-256 fingerprints.
Archive & PDF
ZIP File Integrity Checker
Inspect ZIP directory structure and verify supported entries using decompression and CRC32.
ZIP Archive Contents Viewer
Read filenames, sizes, compression types, and directory metadata from a ZIP.
PDF File Structure Checker
Check PDF header, end markers, and cross-reference pointers for obvious corruption.
Images & Media
PNG Chunk Integrity Checker
Check PNG signature, chunk boundaries, image dimensions and chunk CRCs.
JPG/JPEG Structure Checker
Check JPEG start/end markers and scan markers for apparent truncation.
GIF File Checker
Check the GIF header, logical dimensions, and closing trailer byte.
WebP Structure Checker
Check the RIFF/WEBP container, declared length and known image chunks.
MP4 Container Checker
Inspect MP4 top-level atoms and look for missing or malformed movie metadata.
WAV Audio Header Checker
Inspect RIFF/WAVE headers, declared sizes, and audio format information.
Text & Data
JSON Syntax Repair & Formatter
Validate JSON, optionally fix common trailing-comma/comment issues, and download a clean copy.
CSV Row Repair & Normalizer
Inspect CSV row widths, normalize delimiters, and download repaired CSV.
XML Well-Formedness Checker
Check XML parser errors locally and show actionable syntax diagnostics.
Text File Cleaner
Remove NUL bytes, normalize line endings, and trim trailing whitespace with a downloadable result.
Text Encoding and BOM Checker
Detect UTF byte-order marks, invalid UTF-8 sequences, and unexpected NUL bytes.
Archives & Recovery
Image Diagnostics
Audio & Video
Data File Diagnostics
Safe File Repair
JSON Lines / NDJSON Repair
Find invalid JSONL records and optionally export only valid records into a new file.
Remove PNG Text & EXIF Metadata
Verify PNG chunk CRCs and remove selected text, EXIF and time chunks into a new copy.
Remove JPEG EXIF Metadata Locally
Remove recognized JPEG EXIF APP1 segments without re-encoding image pixels.
Fix WAV RIFF Header File Size
Repair a mismatched WAV RIFF-size field only when all required chunks fit within the file.
Decode / Repair Base64 File
Validate Base64 text, ignore whitespace and missing padding, then download the decoded bytes.