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New: File Converter

Convert files locally — including Word and Excel.

Images, whole PDFs, Word DOCX, Excel XLSX, text, code, CSV and JSON stay on your device. KitLumo never receives or stores a copy.

PDF · Word · Excel · Images

Free Developer tools

Regex Tester

Straightforward tools that work right here on your phone, tablet or computer. No account, no AI, no nonsense.

Your tool data stays on this device. Anything you type, paste, calculate or open in a tool is not sent to us. KitLumo does not receive it or save a copy.
141 free tools Browser-first No account

Free Developer tools

How to use the Regex Tester

Test a regular expression against sample text and review the matches before you put it into production code or a data-cleaning rule.

  1. Enter or choose the information requested by the tool.
  2. Check the result and change an input if you want to compare another scenario.
  3. Copy, download or use the result when it fits your task.

Using the result

Test edge cases as well as normal examples; a pattern that works on one sample can still miss or over-match real data.

Your tool entries are handled in your browser and are not sent to or saved by KitLumo.

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Practical guides

Understand the result, not just the number.

Short, plain-language guides explain the assumptions, privacy and limits behind the most important KitLumo tools.

View all guides
PDF to WordWhat text reflow preserves PDF to ExcelHow pages become worksheets Mortgage paymentsWhat the estimate includes Percentage changeWhich formula answers the question Unit conversionHow to check measurements Calculator checklistHow to check a result

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Format, validate or minify JSON in one place.

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CSV to JSON

Turn comma-separated data into clean, copyable JSON.

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Base64 Converter

Encode or decode text without sending it anywhere.

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URL Encoder

Encode or decode URL text safely in your browser.

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UUID Generator

Generate random UUIDs for software and data work.

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Timestamp Converter

Convert Unix timestamps to readable dates and back.

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Regex Tester

Test a regular expression and inspect every match safely.

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Tool workspace

Word Counter

Help shape KitLumo

Don’t see what you need?

Tell us the task you are trying to solve. The most-requested tools guide what we build next.

How KitLumo stays free

Supported by ads. Helped by people.

Clearly labelled ads fund the website so everyone can use every tool for free. If KitLumo saves you time, you are also welcome to make an optional donation to help pay for hosting and keep the tools available.

Donating never unlocks extra features. Every tool remains free for everyone.
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How it works

Free means free.

KitLumo is built around small, focused utilities. No login walls, no artificial limits and no AI layer where a reliable tool will do.

Every tool currently available works directly on the phone, tablet or computer you are using. Anything you type, paste, calculate or open in a tool is not sent to us, and KitLumo does not save a copy.

Your saved and recently used tool shortcuts are stored only in your browser on this device. When you use “Report a problem” or “Request a free tool,” only that message and any email address you choose to add are sent to KitLumo.

Help shape KitLumo

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