SEO・ライティング・Web制作のための無料ツール — 登録不要・シンプル

Content & Writing Tools

Check, polish and rewrite text before you publish it.

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Plagiarism Checker Scan text against web sources to spot copied or duplicate content. Grammar Checker Catch grammar, punctuation and spelling mistakes as you write. Article Rewriter Rewrite full articles while keeping the original structure and meaning. Word Counter Count words, characters, sentences, paragraphs and reading time instantly. Character Counter Count characters with and without spaces, for tweets, meta tags and captions. Readability Checker Score your text with Flesch-Kincaid and other readability formulas. Paraphrasing Tool Rewrite a sentence or paragraph in different words while keeping the meaning. Case Converter Switch text between UPPERCASE, lowercase, Title Case and Sentence case. Text to Slug Converter Turn a title into a clean, URL-friendly slug.

AI Tools

AI-assisted writing, detection and content generation.

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AI Content DetectorPRO Estimate the likelihood that a piece of text was written by AI. AI HumanizerPRO Rephrase AI-generated text so it reads more naturally. AI Article GeneratorPRO Generate a first draft of an article from a topic and outline. AI Blog Title Generator Get blog title ideas for a topic or keyword. AI SEO Writing AssistantPRO Get on-page suggestions while you draft content for a target keyword. AI Product Description Generator Generate e-commerce product descriptions from a few bullet points. AI Cover Letter Generator Draft a tailored cover letter from your resume and the job description. AI Resume GeneratorPRO Build a clean, ATS-friendly resume from your work history. AI Image GeneratorPRO Generate an original image from a text description. 近日公開

YouTube & Social Media Tools

Titles, tags, bios and hashtags for YouTube, Instagram, TikTok and X.

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YouTube SEO Tool An all-in-one workflow for one video: title/description/tag bundle, real keyword research, competitor analysis, script audit, checklist and rank tracker. YouTube Backlink Generator Generate a list of sites where you can submit a video link. YouTube Title Generator Turn a video topic into click-worthy, search-friendly title options. Hashtag Generator Generate relevant hashtags for Instagram, TikTok and X from a topic. Instagram Bio Generator Build a short, punchy Instagram bio from a few keywords about you. YouTube Tag Generator Generate relevant video tags from your title and topic. YouTube Description Generator Draft a structured video description with timestamps and links. YouTube Channel Name Generator Get available-sounding channel name ideas for your niche. X / Twitter Bio Generator Write a short, punchy X bio within the character limit.

Keyword Tools

Research and track the keywords that matter to your site.

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Keyword Position CheckerPRO Check where a domain currently ranks for a target keyword. Keyword Density Checker See how often each word or phrase repeats on a page. Long-Tail Keyword Generator Expand a seed keyword into longer, more specific search phrases. CPC Calculator Estimate cost-per-click economics for a paid search campaign. Related Keywords Finder Find keywords related to a topic for content planning. Keyword Cannibalization Matrix Compare two URLs to spot overlapping keyword targeting. Topical Authority Cluster Builder Group a raw keyword list into a hub-and-spoke content model. Prompt to Keyword Converter Turn a long conversational AI prompt into trackable SEO keywords. Brand Citation Prompt Generator Get ready-to-use prompts for testing your brand's visibility in ChatGPT and Perplexity.

Technical SEO & Site Management

Keep the technical side of your site healthy.

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Page Speed Checker Check how fast a page loads and what is slowing it down. XML Sitemap Generator Generate an XML sitemap for any small site by crawling its links. Robots.txt Generator Create a robots.txt file with the rules you choose. HTML Minifier Strip unnecessary whitespace and comments from HTML. CSS Minifier Compress CSS to reduce file size. JavaScript Minifier Compress JavaScript files for faster page loads. HTTP Header Checker Inspect the HTTP response headers a URL returns. SSL Checker Check an SSL certificate's validity and expiry date. Redirect Checker Trace a URL's redirect chain and status codes.

Link Building & Domain Research

Research backlinks, domains and link health.

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Backlink CheckerPRO See total backlinks, linking root domains and Domain Authority for any URL. Broken Link Finder Scan a page for links that return an error. Domain Age Checker Look up when a domain was first registered. WHOIS Lookup Look up public registration details for a domain. DNS Lookup Check a domain's DNS records (A, MX, TXT, NS and more). Alexa Rank Checker Check Alexa Rank. Backlink Maker Generate real submission links to a dozen backlink-friendly platforms. Blacklist Lookup Look up Blacklist. Bulk Domain Age Checker Check Bulk Domain Age.

Meta Tag & Social Tools

Control how your pages look in search and social previews.

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Meta Tag Generator Generate title, description and Open Graph tags for a page. Meta Tag Analyzer Fetch a URL and review its existing meta tags. Open Graph Tag Generator Create Open Graph tags so links look right on social media. Schema Markup Generator Generate JSON-LD structured data for common page types. Twitter Card Generator Create Twitter/X Card tags for link previews. Disavow File Generator Generate Disavow File. Open Graph Checker Check Open Graph. Privacy Policy Generator Generate Privacy Policy. Terms and Conditions Generator Generate Terms and Conditions.

Image Tools

Resize, compress and clean up images for the web.

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Image Resizer Resize an image to exact dimensions in the browser. Image Compressor Reduce image file size with minimal quality loss. AI Image Converter Convert between PNG, JPG, WebP, GIF, BMP, TIFF, AVIF, iPhone HEIC, PDF, SVG, ICO and more, in batches, with a smart format suggestion. Image Cropper Crop an image to a chosen aspect ratio. EXIF Data Viewer & Remover View or strip the hidden metadata stored inside a photo. AI Favicon Generator Generate a complete favicon set - every size, a real favicon.ico, manifest and browserconfig - with smart auto-fit for non-square logos. Base64 to Image Base64 to Image — a free online tool. Color Picker Tool Color Picker Tool — a free online tool. Dummy Image Placeholder Dummy Image Placeholder — a free online tool.

Converters & Utilities

Small everyday tools that do not fit anywhere else.

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Unit Converter Convert between length, weight, temperature and more. Password Generator Generate a strong, random password with custom rules. QR Code Generator Turn a link or text into a scannable QR code. Currency Converter Convert between world currencies using current rates. Base64 Encoder / Decoder Encode text to Base64 or decode Base64 back to text. AdSense Calculator Calculate AdSense. Age Calculator Calculate Age. Area Converter Convert Area. Average Calculator Calculate Average.

PDF Tools

Merge, split, convert and edit PDF files, entirely in your browser.

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Merge PDF Combine multiple PDF files into one, in the order you choose. Split PDF Pull specific pages out of a PDF into a new file. Image to PDF Turn one or more images into a single PDF document. PDF to JPG Convert each page of a PDF into a downloadable JPG image. Rotate PDF Rotate one or all pages of a PDF and save a new copy. Remove PDF Pages Delete specific pages from a PDF and download the result. PDF to PNG Convert each page of a PDF into a lossless PNG image. Watermark PDF Stamp a text watermark across every page of a PDF. Add Page Numbers to PDF Add page numbers in the position, format and starting number you choose.

Web3 & Crypto SEO Tools

SEO and marketing utilities built for crypto and blockchain projects.

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Altcoin Volatility Tracker Measure a coin's real 30-day price volatility from live market data. Tokenomics Rich Snippet Generator Format token distribution data into structured, search-friendly HTML. Web3 Domain Authority CheckerPRO Check the search footprint and backlink profile of .eth and crypto domains. 近日公開 DApp Landing Page SEO Grader Audit a decentralized app's landing page against standard SEO factors. Smart Contract Address Trust CheckerPRO Check an Ethereum address's verification status, age and activity on-chain. Crypto Whitepaper Readability Scorer Check whether a whitepaper is readable by non-technical retail investors. Blockchain Explorer Link Extractor Pull outbound links from a blockchain explorer transaction page. Crypto DCA Calculator Calculate your average entry price across multiple purchases. Satoshi to USD Converter Convert small fractions of Bitcoin into your local currency.