# HTML / CSS / JavaScript formatter > Browser-only file conversion. Selected files are processed on this device and are not uploaded to a conversion server. Source: https://localconverter.tech/format-code Format or minify HTML, CSS and JavaScript without executing the source. UTF-8 text up to 1 MB. Processing stays on this computer. Inputs are never executed. Paste UTF-8 text into the main input or upload a matching file. A selected file takes priority over the pasted text. ## Useful tasks - Format HTML, CSS or JavaScript for review. - Minify supported source text for a delivery copy. - Compare readable and compact output without executing the source. ## Steps 1. **Provide the source**: Paste UTF-8 text into the main input or upload a matching file. A selected file takes priority over the pasted text. Read the operation note before starting, because supported syntax and file limits are part of the result contract. The original file is not overwritten or renamed by this workflow. 2. **Choose the intended result**: Review the controls for Source language, Result. Change settings according to the file or text you actually supplied. Defaults are a starting point rather than a promise that every source uses the same conventions. UTF-8 text up to 1 MB. Processing stays on this computer. Inputs are never executed. 3. **Create and inspect the output**: Use the main action button to run html / css / javascript formatter. Local processing checks the source and reports malformed or unsupported inputs. A completed job appears in Your results, with a download action and a preview when the output supports it. If the operation fails, read its message and correct the source or settings before retrying; changing only a filename does not change file contents. 4. **Save and verify the result**: Download the finished output and open it in the application or workflow that will consume it. Enter or upload the source, choose settings, then create and review your result. Check the values, layout, encoding or parsed structure relevant to your task. Keep the source when you may need another set of settings later. Temporary job downloads are session-owned and expire; saving your own copy is the way to retain a result. ## Settings - **Source language**: Choose source language according to the result you need. Available choices: html; css; javascript. The initial selection is html. - **Result**: Choose result according to the result you need. Available choices: format; minify. The initial selection is format. ## Try html / css / javascript formatter with a small source Try this source:

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Local tools

. Use the initial settings, inspect the result and then change one setting to understand its effect. UTF-8 text up to 1 MB. Processing stays on this computer. Inputs are never executed. ## Check the result Enter or upload the source, choose settings, then create and review your result. UTF-8 text up to 1 MB. Processing stays on this computer. Inputs are never executed. Open the saved output in the app or workflow where you plan to use it. Check one representative result before repeating the same settings with more files. The original files stay unchanged. ## Limits - Files are processed on this device. Browser memory and engine-specific limits apply. Save results before reloading. - UTF-8 text up to 1 MB. Processing stays on this computer. Inputs are never executed. - Upload one file with a combined size of at most 100 MB. The completed output must fit within 200 MB. - Pasted text and uploaded text have operation-specific UTF-8 byte limits. Productivity tools accept up to 1 MiB (1,048,576 bytes); non-ASCII characters can use several bytes each. If a file is selected, it takes priority over pasted text. - Selections and completed jobs stay available while you navigate inside this tab. Use My files to revisit results. Reloading or closing the tab clears the workspace; download results you want to keep first. ## Questions ### What does HTML / CSS / JavaScript formatter produce? Format or minify HTML, CSS and JavaScript without executing the source. UTF-8 text up to 1 MB. Processing stays on this computer. Inputs are never executed. ### Which source should I use? Paste UTF-8 text into the main input or upload a matching file. A selected file takes priority over the pasted text. Supported file extensions are txt, md, markdown, json, csv, html, htm, css, js, sql, xml, yaml. The processing engine checks actual contents; a matching extension alone does not make malformed content valid. ### Why did this input fail? UTF-8 text up to 1 MB. Processing stays on this computer. Inputs are never executed. Check syntax, required inputs and the ranges shown next to settings. An error keeps unsupported data from being presented as a successful conversion. Correct the source and retry rather than repeatedly resubmitting an unchanged invalid input. ### How should I check the download? Enter or upload the source, choose settings, then create and review your result. Review the saved content in its destination application, including a typical case and any boundary values important to your use. A completed operation confirms processing finished; it cannot determine whether the supplied settings match your wider business requirements. ### Does HTML / CSS / JavaScript formatter upload files to another service? Processing runs in this browser, on your device. Files and pasted input are not uploaded to a conversion server. The website and required engine assets must load first; large operations depend on available device memory. ### Can I continue after changing pages? Selections and completed jobs stay available while you navigate inside this tab. Use My files to revisit results. Reloading or closing the tab clears the workspace; download results you want to keep first. ## Related guides - [SQL formatter](https://localconverter.tech/format-sql.md) - [Text difference checker](https://localconverter.tech/compare-text.md) - [Markdown live editor](https://localconverter.tech/markdown-editor.md) - [JSON to CSV](https://localconverter.tech/json-to-csv.md) - [JSON to TSV](https://localconverter.tech/json-to-tsv.md)