How SAA Tool works

200 of our 229 tools run entirely in your web browser. The rest look something up on the internet, and this page lists what each one sends and where.

1. Tools that run in your browser

PDF, image, QR code, text, developer, security, calculator and unit converter tools work inside the web page on your own phone or computer. When you choose a file, your browser reads it from your device and the result is made there too. The file isn't uploaded to us or anyone else, and nothing is kept after you close the page. That's also why a large PDF can take longer on an older phone: your device does the work.

Some tools need a code library the first time you use them, such as the PDF reader pdf.js, the PDF writer pdf-lib, JSZip for ZIP files or a QR code library. These libraries download from our own site and then run on your device, so it's still local processing. Your browser usually keeps them for next time.

Category	Tools that load a library from saatool.com
PDF Tools	JPG to PDF, PDF Compare, Compress PDF, PDF to CSV, Delete PDF Pages, PDF to Excel, PDF Page Extractor, PDF Flatten, PDF Form Filler, PDF Grayscale, PDF to HTML, Extract Images from PDF, PDF to JPG, PDF Merge, PDF Metadata Remover, Add Page Numbers to PDF, PDF to PNG, PDF Protect, Reorder PDF Pages, PDF Repair & Checker, Rotate PDF, Split PDF, PDF to Text, PDF Unlock, Add PDF Watermark, PDF to Word, Word to PDF
Image Tools	AVIF to JPG, AVIF to PNG, Favicon Generator, HEIC to JPG, HEIC to PNG, ICO Converter, Image to PDF, Image Watermark, JPG to PNG, JPG to WebP, PNG to JPG, SVG to JPG, SVG to PNG, WebP to JPG
QR Code Tools	Bitcoin QR Generator, Email QR Generator, Calendar Event QR Generator, Location QR Generator, Phone QR Generator, QR Code Generator, QR Color Generator, QR Code Decoder, QR Code with Logo, QR Code Scanner, SMS QR Generator, Plain Text QR Generator, vCard QR Generator, WhatsApp QR Generator, Wi-Fi QR Generator
IT Tools	Cron Expression Explainer, Cron Expression Generator
Developer Tools	CSS Formatter, CSS Minifier, Text Diff Checker, HTML Formatter, JavaScript Formatter, JavaScript Minifier, Markdown to HTML, SQL Formatter, YAML Formatter & Validator, YAML to JSON Converter
Text Tools	Text to PDF

2. Text recognition (OCR)

PDF OCR, Image to Text (OCR) read text with Tesseract, an open-source OCR engine, inside your browser. The first time, the engine (about 4 MB) and the language data (2–5 MB per language) download from jsDelivr, a public network for open-source code. Your PDF or picture is never sent anywhere.

3. Tools that ask a public service from your browser

DNS tools: DNS Lookup, DNS Record Checker, MX Record Checker, TXT Record Checker, SPF, DKIM & DMARC Checker, Reverse DNS Lookup, Domain IP Lookup, ASN Lookup, IP Blacklist Checker, IPv4/IPv6 Compatibility Checker. Your browser sends the domain name or IP address you enter to Cloudflare's public DNS service (1.1.1.1) using DNS over HTTPS. The ASN Lookup uses Team Cymru's public service through DNS, the IP Blacklist Checker asks each blacklist's DNS servers, and the IPv6 check also asks ipify for your addresses.
DNS Speed Test: your browser asks six public DNS services (Cloudflare, Google, Quad9, AdGuard, OpenDNS and NextDNS) directly and times each answer.
Currency Converter: your browser downloads the day's reference rates from ExchangeRate-API (open.er-api.com). The amount and currencies you choose aren't sent.

4. Tools that use our server

A browser can't open a network connection to another computer, test a port or read a certificate on its own, so these tools ask our small server on Cloudflare's network (api.saatool.com) to do it:

IP Address Checker, Internet Speed Test, Download Speed Test, Upload Speed Test, Port Checker, Ping Test, WHOIS Lookup, DNS Propagation Checker, HTTP Status Checker, HTTP Headers Checker, Redirect Checker, Website Uptime Checker, Website Response Time Checker, SSL Checker, SSL Certificate Expiry Checker.

What is sent: only what you type (a domain, IP address, web address or port), plus the usual request details every website sees, such as your IP address. The speed tests send random test data to and from the server.
Where it runs: in the Cloudflare data centre nearest to you, so results can differ slightly from a check made in another country.
What is kept: nothing we store. Cloudflare keeps its standard short security logs. The server counts requests per IP address for one minute to prevent abuse, for example 20 port checks or 10 ping tests a minute.
Safety limits: private and local network addresses are refused, and port 25 (email) is blocked, so the server can't be used to probe home networks or send spam.

5. What we don't do

No accounts and no sign-up.
No storing, reading or selling of your files, text or look-ups.
No cookies of our own. Ads from Google AdSense may use cookies, as the Privacy Center explains.

6. How we test the tools

Each tool is checked in a real browser with sample files and known answers before release, and again with every update: PDFs are opened with two different PDF libraries to confirm they're valid, conversions are compared with exact factors, and money results are compared with worked examples. Each tool page lists its known limits under "Limits and accuracy". If you find a problem, please report it.