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Local processing and network requests

Calculators, file tools and text analysis compute locally with JavaScript. Network tools send the domains, IP addresses or measurement traffic needed for the requested operation to the providers disclosed on their pages.

External requests include fonts, exchange rates, DNS, IP lookups, network measurements and optional SEO URL fetching. See the Privacy Policy for the providers and data involved. You can inspect requests in your browser’s DevTools → Network tab.

Visit counting is first-party and cookieless. A tiny script of ours tells our own server which page was opened, the site you came from, your time zone and language and whether a tool was used (yes/no) — never tool inputs (the query string and fragment are not sent) and never to a third party. The server keeps the page path, a country code and an anonymous visitor number that changes every day, deletes per-visit records after 180 days, and honours Do Not Track / Global Privacy Control; you can switch it off on the Privacy Policy page. The web server’s own access log (page path, time, IP address, browser) also feeds an aggregate report with anonymised IP addresses; the query string is never written to it.

The “Send feedback” button (bottom right) sends your message — and your email, if you add one — to this site’s own server only when you press Send, so we can read and answer it. Feedback is not sent to a third party.

Most tools never ask you to log in. A few beta features (marked “Log in · Beta”) need a Kakao, Naver or Google login; we keep only your nickname, the provider’s account number and login dates, plus how many times you used each beta feature — never your photos or file names. You can log out or delete your account from the account menu at the top. See the Privacy Policy for details.

• Large text inputs (JSON, diffs, word counter…) are kept in this browser’s localStorage so a reload does not lose them. “Clear” removes them.
• The flip side of “nothing is uploaded”: everything lives only in this browser. Clearing site data, using private windows, or switching browsers/devices removes it, and Safari may drop it after 7 days without a visit. Tools that accumulate records (subscription tracker, card spending tracker…) show a storage notice and offer Export/Import — use Export as your backup.
• Regex and Diff share their state in the URL fragment (after #), which browsers never send to servers.
• File tools work offline once the page has loaded.

Using a tool

• Results update as you type — there is no Calculate button. Heavy file operations have an explicit run button.
• Every result has a Copy button. The Share link button copies a URL that reproduces your current inputs.
• Each tool page ends with “How to use” steps and an FAQ.
• Enter numbers freely: 1,000, $50, 15% and −3 are all understood.

Language, units, text size and theme

• Language is detected from your browser (then your time zone). Change it any time with the selector in the header; the choice is remembered on this device.
• Units and currency default to your language’s country (metric / imperial, °C / °F, KRW / USD…). Override them site-wide with the ⚖ button in the header, or per tool inside the tool itself. A value in a shared link always wins.
• Text size: the Aa button offers Default, Medium and Large for easier reading. The whole site scales.
• Theme follows your system and can be toggled with the sun/moon button.

Shortcuts and favourites

• Press / anywhere to jump to the search box; use ↑ ↓ and Enter to open a result.
• Ctrl/Cmd + Enter runs the action in tools that have one (e.g. Format JSON).
• ☆ Save on a tool page pins it to “Your tools” on the home page; recently used tools appear there automatically.

File tools: formats and limits

• Images: JPG, PNG, WebP, GIF, BMP and SVG can be read; output is JPG, PNG or WebP. HEIC/AVIF output is not supported by browsers without a large codec, so it is not offered.
• PDF: merge, split, rotate, images → PDF and PDF → images. Encrypted PDFs must be unlocked first; compression and passwords are intentionally not offered because browser libraries cannot do them reliably.
• There is no file-count or size limit, but very large files depend on your device’s memory. If a file fails, the row shows the reason.
• Download all as ZIP bundles every result in one file.

Accuracy

Formulas follow standard definitions (e.g. WHO BMI bands, exact SI conversion factors, cent-precision amortization). Finance results are estimates for planning, not offers; exchange rates are daily ECB reference rates, not bank rates.

Copyright & third-party licences

© 2026 너멜엠 NumLM. The site’s own code, texts, design and the NL mark are copyrighted — all rights reserved. The tools can be used for personal and commercial purposes; copying the site or its code is not permitted.

The site is built on the open-source components below. Each is used under its own licence, whose terms and copyright notices are kept as required:

• kordoc — MIT (bundle notices) · Document-converter engine (HWP/HWPX/HML/PDF/XLSX/DOCX parsing, HWPX generation) — runs locally as a Web Worker; its bundle notices cover pdfjs-dist, jszip, @xmldom/xmldom, cfb, zod, fflate and buffer
• fflate — MIT · ZIP packaging for the Word (.docx) and Excel (.xlsx) files the document converter creates
• libheif-js / libheif / libde265 — LGPL-3.0 (notices and source) · Local HEIC decoding; licence texts, corresponding source and replacement instructions
• Mediabunny — MPL-2.0 · Reads MP4, MOV, MKV, WebM and MPEG-TS videos; copies their sound track without re-encoding (video-to-audio tools), compresses or converts video with the browser's encoder (video compressor and MP4 converters) and writes the masked H.264 video plus copied AAC packets of the video face-blur tool into its output MP4; bundled unmodified — source code at the link
• MediaPipe Tasks Vision + BlazeFace · Face Landmarker models — Apache-2.0 · Face detection and outline verification in the video face-blur tool (WebAssembly in a Web Worker, on your device); runtime 0.10.22-rc.20250304, models and WASM unmodified; finds where faces are — no identity recognition, no face embeddings stored
• mp4box.js 0.5.4 — BSD-3-Clause · MP4 parsing (tracks, timestamps, AAC packets) for the video face-blur tool; bundled unmodified
• lamejs / LAME — LGPL-3.0 (notices and source) · MP3 encoding in the audio converter and the video-to-audio tools, loaded unmodified as a separate file — uses LAME (lame.sourceforge.io); licence texts, corresponding source and replacement instructions
• Ambient sound loops and the cuckoo alarm (ElevenLabs Sound Effects) — Generated under a paid plan (ElevenLabs Terms of Use §1(c), §4(c)(ii)) · The rain, thunder, wind, waves, campfire, stream, crickets, birds and cafe loops of the time tools’ focus environment (/sounds/ambient/) and the Cuckoo alarm clip (/sounds/time/cuckoo.mp3) were generated with the ElevenLabs Sound Effects API under a paid plan and are served from this site only; the other alarm cues and the noise, fan and heartbeat sounds are synthesised in the browser. Details: docs/focus-sounds-licensing.md in the repository
• libflac.js / libFLAC / libogg — MIT, BSD-3-Clause · FLAC encoding in the audio converter (WebAssembly, runs locally in a Web Worker); notices include Emscripten
• Svelte / SvelteKit — MIT · UI framework the site is built with
• Lucide Icons — ISC · All icons
• Noto Sans KR — SIL OFL 1.1 · Web font (served by Google Fonts)
• PDF.js (pdfjs-dist) — Apache-2.0 · PDF rendering and PDF → image in PDF Tools
• pdf-lib — MIT · PDF merge, split, rotate and image → PDF
• JSZip — MIT · ZIP download of multiple files, including the audio converter (dual MIT/GPL-3.0; used under MIT)
• UPNG.js — MIT · PNG quantisation in the Image Compressor
• node-qrcode — MIT · QR Code Generator
• jsdiff — BSD-3-Clause · Text Diff
• js-md5 — MIT · MD5 in the Hash Generator (SHA via Web Crypto) and the audio converter lossless check
• gpt-tokenizer — MIT · o200k_base / cl100k_base BPE tokenizers in the LLM Token Counter
• Faker (@faker-js/faker) — MIT · English and Korean name, address and text data in Dummy Data Generator
• korean-lunar-calendar — MIT · Korean lunar ↔ solar conversion in the Age Calculator
• Frankfurter · European Central Bank — Open data · Daily exchange-rate table for the Currency Converter

Feedback

Found a bug or missing a tool? Use the “Send feedback” button at the bottom right of any page.