XLSX to HTML

Document conversion online is the process of transforming a file from one format to another directly in your browser — no software to install, no account required. Transfonic supports 13 document formats, including PDF, DOCX, XLSX, PPTX, CSV, HTML, EPUB, ODT, ODS, RTF, TSV, TXT, and Markdown, converting between them in seconds for free.

Converting an Excel spreadsheet to CSV — or bringing a CSV file back into Excel — is one of the most common data tasks people run into. Whether you need to import data into a database, feed a file into an analytics tool, or share clean data with a developer, this guide covers every method, every problem, and every question you will run into.

If you've ever tried to upload an image and been told the file is "too large" or "wrong format," you already know why converting between PNG and JPG matters. These are the two most common image formats on the planet, and switching between them is one of those small tasks that should be simple — but most guides bury the answer under software ads and confusing jargon. This guide fixes that. You'll learn how to convert PNG to JPG and JPG to PNG using the free tools already built into your Mac and Windows PC, how to do it on your phone, and the fastest way to convert one image or hundreds at once in your browser. We'll also clear up the single biggest myth about this conversion — the one almost every tutorial gets wrong. If you just want it done right now, you can convert PNG to JPG online or use the JPG to PNG converter — both run in your browser, free, with no signup and no files ever uploaded to a server. Otherwise, read on for every method.

Converting a text file to CSV is one of the most common data tasks there is — and also one of the most misunderstood. The actual file format difference between TXT and CSV is smaller than most people think. Both are plain text. Both store data as characters. The difference is structure: a CSV file uses commas to separate values into columns and line breaks to separate rows, following a defined pattern that every spreadsheet, database, and analytics tool understands natively. A plain TXT file might have that same structure already — values separated by tabs, pipes, spaces, or commas — but saved with the wrong extension or without the standard delimiter that downstream tools expect. Converting it to CSV means reformatting the delimiter into standard comma separation and saving the result with a .csv extension so every tool opens it correctly. This guide covers every method: a free online converter for quick single-file conversions, Microsoft Excel's built-in import wizard for structured workflows, and Python for batch or automated processing. It also covers the most common problems — encoding errors, misaligned columns, and delimiter confusion and how to fix them.