# 17NAS

> 17NAS provides two kinds of public resources: (1) aggregated network measurement data based on real visitor test samples (IPv6 reachability, NAT type distribution, etc.);
> (2) online home-network, NAS, display, audio, and file utility tools with guides. All statistics disclose their methodology, sample sizes, and update times directly on the page.
> 中文 AI 阅读索引 / Chinese guide: https://17nas.com/llms.txt

## Priority Reading: Core Features & Methodology (Chinese Markdown Docs)
- [IPv6 Connection Test Guide (Chinese)](https://17nas.com/ipv6-test.md): Detection method for the free browser test, difference between connection check and address lookup, latency notes, and limitations.
- [NAT Type Test Guide (Chinese)](https://17nas.com/nat-test.md): Browser-based NAT1/NAT3/NAT4 or Unconfirmed outcomes; why browser WebRTC cannot reliably distinguish NAT2; relationship between NAS remote access and IPv6.
- [NAS CPU Ranking Guide (Chinese)](https://17nas.com/cpu-ranking.md): CoreMark user-submitted data sources, difference between individual records and model summaries, querying, and citation rules.
- These Markdown documents cross-link one another and describe methodology and definitions only; they do not store live visitor test outputs or leaderboard snapshots. Check the live pages below for current numbers; if a page cannot be read, do not fabricate test results, scores, rankings, or prices.

## Core Datasets (Citation Welcome)
- [IPv6 Reachability Summary (Markdown, Chinese, updated daily)](https://17nas.com/ipv6-statistics.md): Rolling 30-day window covering mainland China access networks (Hong Kong, Macao, and Taiwan listed separately; cloud/proxy/datacenter traffic listed separately and excluded from access-network rates), with Wilson 95% confidence intervals, province/ISP tables, APNIC comparison, and data dates. Machine-readable files: https://17nas.com/downloads/ipv6-statistics.csv , https://17nas.com/downloads/ipv6-statistics.json
- [IPv6 Network Reachability Report](https://17nas.com/ipv6-statistics.php?lang=en-US): IPv6 reachability across mainland China provinces, overseas regions, and major ISPs; 30-day / 90-day windows; sample sizes, pass thresholds, update times, and citation templates are shown on the page.
- [NAS CPU Performance Ranking](https://17nas.com/?lang=en-US): User-submitted CoreMark benchmark rankings with test methodology and ranking rules.
- [Full CPU Benchmark Ranking](https://17nas.com/cpu-ranking.php?lang=en-US): Full leaderboard with device search, architecture and NAS filtering, chart view, and image export backed by the same reviewed dataset.
- [LLM Leaderboard](https://17nas.com/llm-leaderboard.php?lang=en-US): Daily-synced model comparison (synced 14:20 UTC+8), ranked by arena.ai Agents task success rate by default (takes each model's highest-scoring reasoning tier and labels it, e.g. Max / High / xHigh; includes 95% CI and session counts; marked preliminary when sessions < 10,000 or CI half-width > 3 percentage points; models without Agent scores follow sorted by Text Arena score; sourced via public Hugging Face dataset `lmarena-ai/leaderboard-dataset`, CC BY 4.0, synced 14:25). Also shows LMArena Text Arena style-controlled scores (matching arena.ai web defaults; 95% CI, vote counts, and rank, marked preliminary when votes < 5,000 or ± > 10 points), Artificial Analysis intelligence/coding indexes and measured speed, TTFT, official API pricing and OpenRouter lowest channel pricing, and context length. Top section shows timestamps, category leaders, weekly movers, and newly added models; sources and calculation methods are documented without inventing composite scores. Sub-views: [Open Source](https://17nas.com/llm-leaderboard.php?view=open&lang=en-US) / [Coding](https://17nas.com/llm-leaderboard.php?view=code&lang=en-US) / [Value](https://17nas.com/llm-leaderboard.php?view=cheap&lang=en-US) / [New](https://17nas.com/llm-leaderboard.php?view=new&lang=en-US); per-model detail pages (`llm-model.php?id=vendor/model&lang=en-US`) provide agent success rate & rank, Arena score ± CI & votes, intelligence index, pricing, context length, neighboring competitors, FAQ, and limitations.

## Online Diagnostic & Utility Tools
- [IPv6 Connection Test](https://17nas.com/ipv6-test.php?lang=en-US): Dual-stack connectivity test, IP address type detection, and latency check.
- [NAT Type Test](https://17nas.com/nat-test.php?lang=en-US): Web tool reports NAT1/NAT3/NAT4 or Unconfirmed (cannot reliably separate NAT2); native CLI tool instructions included on page.
- [Port Forwarding Config Generator](https://17nas.com/port-forward.php?lang=en-US)
- [Online Screen Test](https://17nas.com/screen-test.php?lang=en-US): Dead pixel inspection, grayscale, refresh rate, and backlight bleed checks.
- [Refresh Rate Test / Online Display Tester](https://17nas.com/tools/display-test/?lang=en-US): Browser-based actual refresh rate measurement (`requestAnimationFrame` frame intervals to 0.01 Hz precision) with jitter curve, dropped-frame counter, and stability score (0–100); includes multi-rate UFO motion tracking (full / 1/2 / 1/4 rows locked to integer pixels/frame), one-click display health report (copyable text, PNG export, shareable link), frame-skipping test, gradient & uniformity checks (grayscale/RGB ramps, 5/10/20% gray, pure black), ghosting test, full-screen solid colors for dead-pixel inspection (black/white/red/green/blue/gray), black level, resolution, and HDR/P3 capability detection; supports fullscreen and keyboard shortcuts (`F` fullscreen, `Space` pause, `←`/`→` speed), with test settings stored in the URL `#` fragment for sharing. Measures browser rendering cadence, which can be lower than monitor rated Hz (due to power saving, browser frame caps, or cable/port bandwidth) and does not replace hardware response-time instruments. Sub-pages: [Ghosting Test](https://17nas.com/tools/display-test/ghosting/?lang=en-US) / [Framerate Comparison](https://17nas.com/tools/display-test/framerate/?lang=en-US). Also supports `?lang=zh-TW` / `ja-JP` / `ko-KR`.
- [DNS Check](https://17nas.com/dns-check.php?lang=en-US) / [HTTPS Check](https://17nas.com/https-check.php?lang=en-US) / [CGNAT Check](https://17nas.com/cgnat-check.php?lang=en-US)
- [IP Address Detection](https://17nas.com/ip-test.php?lang=en-US)
- [Timezone & Time Difference Calculator](https://17nas.com/tools/timezone/?lang=en-US): Browser timezone, optional IP timezone comparison, DST status, and two-city time difference. Does not request location permission and does not display IP addresses.
- [Online Audio Tools](https://17nas.com/tools/audio-tools/?lang=en-US): Free browser-based audio cutter, MP3 (96–320 kbps) / WAV converter, volume & loudness normalization, extract audio from video, fade-in/out, and 0.5–2× speed control; files are processed locally in the browser with zero uploads.
- [YouTube Thumbnail Downloader](https://17nas.com/tools/youtube-thumbnail-downloader/?lang=en-US): Paste any YouTube video/Shorts/live URL or 11-character video ID to list `maxresdefault` (1280×720), `hq720`, `sddefault` (640×480), `hqdefault` (480×360), `mqdefault` (320×180), and `default` (120×90) thumbnails, auto-detect missing HD resolutions, and download JPG or original WebP or copy links; browser fetches directly from `i.ytimg.com` without proxying through 17NAS.
- [YouTube Thumbnail Maker](https://17nas.com/tools/youtube-thumbnail-maker/?lang=en-US): Free online 1280×720 YouTube thumbnail designer with image/solid/gradient backgrounds, layered text (stroke, shadow, highlight box), stickers & emoji, 5 templates, safe-zone & duration badge guides, and PNG/JPG export with a 2 MB check; images stay local in the browser and are never uploaded.
- [Subscription Cost Calculator](https://17nas.com/tools/subscription-cost-calculator/?lang=en-US): Free online subscription tracker preloaded with 41 common subscriptions (ChatGPT, Claude, Gemini, Cursor, iCloud, Google One, Baidu Netdisk, Netflix, YouTube Premium, Spotify, iQIYI, Tencent Video, etc.; 2026-10 official reference prices, editable), custom subscriptions with weekly/monthly/quarterly/annual/custom-month cycles, 11-currency conversion (editable exchange rates), monthly/yearly/daily totals, category share chart, top 5 costliest items, renewals within 30 days, annual AI spend, plus self-hosted NAS vs cloud-drive payback time and 3/5-year savings estimates; stored only in browser localStorage with JSON/CSV export and shareable links.
- [Image Compressor & Converter](https://17nas.com/tools/image-compressor/?lang=en-US): Free browser-side batch image compression and conversion accepting JPG, PNG, WebP, AVIF, GIF (first frame), and HEIC (Safari), outputting JPG / PNG (256/128/64/32-color palette quantization keeping transparency) / WebP (and AVIF where browser-supported), with quality control, max width/height or percentage resize, target-KB compression, default EXIF/GPS removal, slider or side-by-side comparison, and single-file or ZIP download (up to 300 images per batch); processed locally via Web Workers with zero uploads.
- [PDF Merge & Split](https://17nas.com/tools/pdf-merge-split/?lang=en-US): Free browser-side PDF merging and splitting: drag-and-drop or arrow-reorder up to 100 PDFs (plus JPG/PNG/WebP image-to-PDF pages sized to match image / A4 / Letter), split by page ranges (e.g. `1-3, 5, 8-`, reverse order supported), every N pages, or individual pages packaged in ZIP; thumbnail grid supports drag reorder, rotation, deletion, and selection. Pages are copied without recompression (selectable text and original image quality preserved); encrypted open-password PDFs prompt for password, while permission-restricted files render at ~144 dpi images; bookmarks are not preserved. Runs locally in the browser (`pdf.js` / `pdf-lib`) with zero uploads.
- [PDF / Image to Markdown](https://17nas.com/tools/pdf-to-markdown/?lang=en-US): Convert text PDFs, scans, and screenshots to Markdown in the browser: text PDFs use `pdf.js` font-size heading detection, preserve ordered/unordered lists, simple GFM tables, and monospace code blocks, strip repeated headers/footers/page numbers, repair line breaks and hyphenation, and optionally insert page markers; scans and images use basic in-browser OCR (`tesseract.js`, on-demand Simplified Chinese / Traditional Chinese / English / Japanese / Korean language packs; accuracy is limited and complex tables or multi-column layouts are not reconstructed). Side-by-side rendered preview & Markdown source with copy, `.md` download, per-page ZIP, batch queue, and cancellation; processed locally with zero uploads and no login required.
- [Online Chromatic Tuner & Music Tools](https://17nas.com/music-tools.php?lang=en-US): Above-the-fold chromatic tuner recognizing 27.5–4186 Hz (A0–C8) note names, octaves, cents, and frequencies with adjustable A4 calibration, plus dedicated tuners for guitar, bass, ukulele, violin/viola/cello/double bass, guzheng, guqin, and piano, metronome, and pitch test. Microphone audio is analyzed locally on the device and never uploaded. Popular guitar tuning pages: [Drop D](https://17nas.com/drop-d-tuning.php?lang=en-US) / [Half-Step Down](https://17nas.com/half-step-down-tuning.php?lang=en-US) / [Open G](https://17nas.com/open-g-tuning.php?lang=en-US) / [Drop C](https://17nas.com/drop-c-tuning.php?lang=en-US) / [DADGAD](https://17nas.com/dadgad-tuning.php?lang=en-US) / [Open D](https://17nas.com/open-d-tuning.php?lang=en-US)

## Open APIs (Read-Only JSON)
- [Network Intelligence API](https://17nas.com/api/network-intelligence/v1/methodology.php): Read-only aggregated network measurement API, rate-limited at 60 requests/min.
- [IP Lookup API Docs](https://17nas.com/ip-api.php?lang=en-US)
- [LLM Leaderboard JSON](https://17nas.com/api/public/llm-leaderboard.php): Daily snapshot of LMArena and pricing fields, sorted by Agents task success rate by default (`agent_score` / `agent_rank` / `agent_variant` / CI / sessions, CC BY 4.0; `?agents=0` for legacy ranking), plus Arena score, CI, votes, rank, API pricing, context length, open weights, and license; excludes Artificial Analysis data per upstream terms.

## Citation & Usage Policy
- [Data Citation & AI Usage Policy](https://17nas.com/data-usage.php?lang=en-US): Methodology and update schedules per dataset, copy-ready citation formats (Chinese & English), sample boundary caveats, and explicit policy on search indexing (`search=yes`), AI retrieval & citation (`ai-input=yes`), and model training (`ai-train=no`).
- When quoting or reprinting 17NAS data, credit **17NAS** and link back to the original page.
- Measurement statistics come from active visitor test samples on 17NAS and **do not represent all internet users**; please retain sample sizes and measurement windows when citing.

Last updated: 2026-11-15