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Type an extension to see what opens it, the steps for the device you have, and what tends to get lost in conversion.
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FIND YOUR FORMAT
Browse every format →Common file formats
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document-office.DOCDOC file: identify, open, assess, and convert an older Word documentDOC is a binary document format that stores Microsoft Word content in an OLE Compound File Binary container, commonly used by Word 97 through Word 2003.↗document-office.DOCMDOCM File: How to Open, Check, and Convert ItA DOCM file is an XML-based Microsoft Word document that can contain VBA macros, with embedded VBA functionality lost when it is converted to DOCX.↗document-office.DOCXDOCX file: what it is and how to open itA DOCX file is a Microsoft Word-processing document in the Office Open XML format. Open it with a DOCX-compatible word processor on a computer or a compatible document app on a phone or tablet. If the file is unexpected, treat it cautiously: the DOCX extension and a ZIP header alone do not establish identity or safety.↗image.HEICHEIC file formatHEIC is an image container that efficiently stores still images and is commonly used by Apple devices, but some systems require compatible HEIF support to open it.↗document-office.ODTODT File: What It Is, How to Open It, and Conversion LimitsODT is a word-processing document format that stores XML content and associated binary data in a ZIP package, with some features or formatting potentially changing between applications.↗document-office.PDFPDF file: identify, open, assess, and convertA PDF file is a document format that represents electronic documents independently of their creation, viewing, or printing environment, but its name or extension does not prove structural validity or safety.↗document-office.PPTPPT file: how to open, check, and convert itPPT is a binary presentation format that stores PowerPoint 97–2003 slides, masters, notes, handouts, OLE objects, and optional VBA projects, with web editing requiring conversion to a newer format.↗document-office.PPTXPPTX File: What It Is, How to Open It, and Conversion LimitsPPTX is an XML-based office presentation format that stores slides and related resources in a ZIP package, with VBA macros requiring a different extension such as PPTM.↗document-office.RTFRTF file: what it is, how to open it, and conversion limitsRTF is a document format that exchanges formatted text and graphics between applications and operating systems, but newer document features and exact layout may not be preserved.↗document-office.XLSXLS File: What It Is, How to Open It, and How to Convert ItXLS is a binary spreadsheet format that stores BIFF5 or BIFF8 workbook records in an OLE Compound File container; saving a newer workbook back to XLS can omit data or features.↗document-office.XLSMXLSM File: How to Open, Check, and Convert ItXLSM is a macro-enabled Microsoft Excel workbook format that stores spreadsheet data and may contain VBA code or Excel 4.0 macro sheets, so its active content requires caution.↗document-office.XLSXXLSX File: How to Open, Check, and Convert an Excel WorkbookAn XLSX file is an Office Open XML SpreadsheetML workbook. Microsoft Excel has used .xlsx as its default format for new workbooks since Excel 2007. Current desktop Excel can open, edit, and save XLSX files; Excel for the web and Microsoft’s mobile Excel apps can also open them.↗
OPEN IT IN YOUR BROWSER
Browse every online tool →Online file viewers
Only viewers that are built and tested are listed here. The ones marked local never send your file anywhere.
RUNS LOCALLY.txtBase64 Encoder & DecoderThe Base64 Encoder & Decoder is a browser-local converter that turns a Base64 string into readable text or downloadable bytes and turns text or a file back into Base64, with a 2,000,000-byte ceiling on the decoded payload.↗RUNS LOCALLY.csvCSV & TSV ViewerCSV Viewer is a browser-local table viewer that opens CSV and TSV files up to 5 MB, detects the delimiter from the header row, and shows every field exactly as written — never converting a value into a number or a date.↗RUNS LOCALLY.*File Hash & Checksum VerifierFile Hash & Checksum is a browser-local verification tool that computes the SHA-256, SHA-384 or SHA-512 digest of a file and compares it with an expected checksum, hashing up to 100 MB per file without the bytes ever leaving the tab.↗RUNS LOCALLY.jsonJSON ViewerJSON Viewer is a browser-local file viewer that opens, formats and checks JSON and JSONL files, with every byte processed in your own browser and nothing uploaded.↗RUNS LOCALLY.txtText & Markdown ViewerText & Markdown Viewer is a browser-based file viewer that opens TXT, Markdown and log files with a reading view, a source view and search, limited to UTF-8 text of up to 2 MB.↗
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