# FernTool

> Fast, free tools: what is my IP (IPv4/IPv6, ISP, ASN, location, timezone), IP lookup with VPN/Tor/datacenter detection, WHOIS (RDAP), DNS, DNS propagation checker, SPF/DKIM/DMARC email security checker, SPF record generator, email header analyzer, is-it-down website checker, redirect checker (where does this link go?), reverse DNS, subnet calculator, speed test, converters, Unix timestamps, date maths, time zones, random numbers, a name picker wheel and a percentage calculator. Free JSON API (no key, CORS *) and an MCP server for AI agents.

## API
- [Your IP, plain text](https://www.ferntool.com/ip)
- [Your IP, JSON](https://www.ferntool.com/json)
- [Look up / validate any IP](https://www.ferntool.com/api/ip/8.8.8.8): GET /api/ip/{ip}
- [OpenAPI spec](https://www.ferntool.com/openapi.json)
- [Batch IP lookup](https://www.ferntool.com/api): POST /api/batch {"ips":[...]} (max 100)
- [WHOIS / RDAP](https://www.ferntool.com/api/whois/example.com): GET /api/whois/{domain|ip|asn}
- [DNS lookup](https://www.ferntool.com/api/dns/example.com?type=A,MX): GET /api/dns/{domain}?type=A,AAAA,MX,TXT,NS,CNAME,SOA
- [Reverse DNS](https://www.ferntool.com/api/reverse-dns/1.1.1.1): GET /api/reverse-dns/{ip}
- [DNS propagation](https://www.ferntool.com/api/dns-propagation/example.com?type=A): GET /api/dns-propagation/{domain}?type=A|AAAA|CNAME|MX|TXT|NS (authoritative vs 8 public resolvers)
- [Email security](https://www.ferntool.com/api/email-security/example.com): GET /api/email-security/{domain}?selector= (SPF incl. 10-lookup count, DMARC, DKIM; verdict + fixes)
- [Is it down?](https://www.ferntool.com/api/is-it-down?url=example.com): GET /api/is-it-down?url= (DNS + one HTTP load, status code, response time, verdict)
- [Redirect checker](https://www.ferntool.com/api/redirects?url=youtu.be/dQw4w9WgXcQ): GET /api/redirects?url= (every hop, final URL, scam warning signs, tracking-free URL)
- Website legit / scam checker: https://www.ferntool.com/api/website-legit?url= (domain age, look-alike brand names, HTTPS, email; verdict no_signs/mostly_ok/caution/likely_scam)
- Email header analyzer: POST https://www.ferntool.com/api/email-headers {"headers":"..."} (is this email real? SPF/DKIM/DMARC, Reply-To tricks, hops, sending IP; verdict verified/unverified/suspicious)
- [SPF record generator](https://www.ferntool.com/api/spf-record?services=microsoft365,mailchimp,website): GET /api/spf-record?services=&domain=&ip=&include=&strict=1 (one valid SPF record, live 10-lookup count)
- [Subnet calculator](https://www.ferntool.com/api/subnet?cidr=192.168.1.0/24): GET /api/subnet?cidr=&split= (split e.g. 64 lists the /64s in a /48)
- [Port check](https://www.ferntool.com/api/port-check?host=example.com&port=443): GET /api/port-check?host=&port= (common TCP ports, 10/min)
- [MAC vendor](https://www.ferntool.com/api/mac/3C22FB): GET /api/mac/{mac}
- [User agent](https://www.ferntool.com/api/user-agent): GET /api/user-agent
- [QR code SVG](https://www.ferntool.com/api/qr?text=https://example.com): GET /api/qr?text=&ecc=L|M|Q|H&fg=000000&bg=ffffff&margin=4[&format=json]
- [Current time / Unix timestamp converter](https://www.ferntool.com/api/timestamp?value=1760000000&tz=Africa/Johannesburg): GET /api/timestamp?value=&tz= (omit value for now)
- [Date calculator](https://www.ferntool.com/api/date-calc?start=2026-10-18&end=2026-12-25): GET /api/date-calc?start=&end=[&include_end=true] or ?start=&add_days=|add_weeks=|add_months=|add_years=[&business_days=true]
- [Time zone converter](https://www.ferntool.com/api/timezone?time=2026-10-19%2015:00&from=Africa/Johannesburg&to=America/New_York,Europe/London): GET /api/timezone?time=&from=&to=a,b (zones, abbreviations like SAST/EST or cities)
- [Random numbers](https://www.ferntool.com/api/random?min=1&max=49&count=6&unique=true&sort=asc): GET /api/random?min=&max=&count=&unique=&sort= (cryptographically secure)
- [Random picker](https://www.ferntool.com/api/pick?items=Ann,Ben,Cara&count=1): GET /api/pick?items=a,b,c&count=&mode=pick|shuffle|teams&teams=&dedupe= (or POST JSON {items:[...]})
- IP results include flags: is_tor, is_datacenter, provider; and timezone
- MCP server (streamable HTTP, POST JSON-RPC): https://www.ferntool.com/mcp — tools: get_my_ip, lookup_ip, batch_lookup_ip, validate_ip, whois_lookup, dns_lookup, reverse_dns, check_dns_propagation, check_email_security, check_website_status, trace_redirects, check_website_legit, analyze_email_headers, generate_spf_record, subnet_calc, estimate_ai_cost, ai_service_status, make_qr_code, count_words, get_current_time, convert_timestamp, date_calc, convert_timezone, random_number, pick_random
- [AI service status JSON](https://www.ferntool.com/api/ai-status): GET /api/ai-status[?service=chatgpt|claude|gemini|copilot|perplexity|cohere]

## Pages
- [What is my IP](https://www.ferntool.com/)
- [Internet speed test (download, upload, ping, jitter)](https://www.ferntool.com/speed-test)
- [IP lookup with VPN/Tor/datacenter check](https://www.ferntool.com/ip-lookup)
- [WHOIS lookup](https://www.ferntool.com/whois-lookup)
- [DNS lookup](https://www.ferntool.com/dns-lookup)
- [DNS propagation checker: has my DNS change updated yet? (authoritative vs Google, Cloudflare, OpenDNS and more, with remaining cache time)](https://www.ferntool.com/dns-propagation-checker)
- [SPF, DKIM & DMARC checker: can anyone fake email from my domain? (plain verdict, SPF lookup count, records to add)](https://www.ferntool.com/spf-dmarc-checker)
- [Is it down for everyone or just me? (server check plus a check from your own browser)](https://www.ferntool.com/is-it-down)
- [Where does this link go? Redirect checker and short link expander with scam warning signs](https://www.ferntool.com/redirect-checker)
- [Is this website legit? (scam website checker)](https://www.ferntool.com/website-legit-checker)
- [Email header analyzer: is this email real or fake? (who really sent it, SPF/DKIM/DMARC, route, sending server on a map)](https://www.ferntool.com/email-header-analyzer)
- [SPF record generator: combine Microsoft 365, Google, newsletters and your website into one SPF record](https://www.ferntool.com/spf-record-generator)
- [Reverse DNS lookup](https://www.ferntool.com/reverse-dns)
- [Subnet calculator (IPv4/IPv6)](https://www.ferntool.com/subnet-calculator)
- [IPv6 subnet calculator: split a /48 or /56 into /64s](https://www.ferntool.com/ipv6-subnet-calculator)
- [IPv6 test](https://www.ferntool.com/ipv6-test)
- [VPN leak test (WebRTC)](https://www.ferntool.com/vpn-leak-test)
- [Open port checker (TCP, common ports)](https://www.ferntool.com/port-checker)
- [Password generator (client-side)](https://www.ferntool.com/password-generator)
- [QR code generator: links, Wi-Fi, email, phone, SMS; static codes that never expire; PNG/SVG](https://www.ferntool.com/qr-code-generator)
- [Word counter: words, characters, sentences, reading time, social/SEO limits](https://www.ferntool.com/word-counter)
- [What is my screen resolution (CSS + physical pixels, scaling, aspect ratio)](https://www.ferntool.com/what-is-my-screen-resolution)
- [Unix timestamp converter: current epoch time, timestamp to date and back, any time zone](https://www.ferntool.com/unix-timestamp-converter)
- [Days between dates calculator: days, weeks, months, working days; add or subtract days](https://www.ferntool.com/days-between-dates)
- [Time zone converter: any two cities or zones, daylight saving handled, meeting planner, world clock](https://www.ferntool.com/time-zone-converter)
- [Random number generator: any range, no repeats, coin flip, dice](https://www.ferntool.com/random-number-generator)
- [Random name picker: spin the wheel, pick winners, shuffle a list, make random teams](https://www.ferntool.com/random-name-picker)
- [Percentage calculator: % of a number, % change, add or remove VAT, discounts](https://www.ferntool.com/percentage-calculator)
- [What is my user agent](https://www.ferntool.com/user-agent)
- [MAC address vendor lookup (IEEE OUI)](https://www.ferntool.com/mac-address-lookup)
- [Ping test (latency, jitter)](https://www.ferntool.com/ping-test)
- [Packet loss test (loss, late packets, latency, jitter; gaming/VoIP/video/streaming presets; best-effort HTTPS probes)](https://www.ferntool.com/packet-loss-test)
- [Unit converters](https://www.ferntool.com/convert)
- [AI cost calculator: tokens, words and USD cost on OpenAI, Claude, Gemini; does it fit](https://www.ferntool.com/ai-cost-calculator)
- [ChatGPT token counter](https://www.ferntool.com/chatgpt-token-counter)
- [ChatGPT word limit checker](https://www.ferntool.com/chatgpt-word-limit)
- [Is ChatGPT down? Live AI status (official status pages)](https://www.ferntool.com/is-chatgpt-down)
- [Is Claude down?](https://www.ferntool.com/is-claude-down)
- [Is Gemini down?](https://www.ferntool.com/is-gemini-down)
- [cm to inches converter](https://www.ferntool.com/convert/cm-to-inches)
- [kg to lbs converter](https://www.ferntool.com/convert/kg-to-lbs)
- [Celsius to Fahrenheit converter](https://www.ferntool.com/convert/celsius-to-fahrenheit)
- [km to miles converter](https://www.ferntool.com/convert/km-to-miles)
- [feet to meters converter](https://www.ferntool.com/convert/feet-to-meters)
- [ounces to grams converter](https://www.ferntool.com/convert/ounces-to-grams)
- [liters to gallons converter](https://www.ferntool.com/convert/liters-to-gallons)
- [MB to GB converter](https://www.ferntool.com/convert/mb-to-gb)
- [Mbps to MB/s converter](https://www.ferntool.com/convert/mbps-to-mbs)
- [mph to km/h converter](https://www.ferntool.com/convert/mph-to-kmh)
- [ml to cups converter](https://www.ferntool.com/convert/ml-to-cups)
- [m² to sq ft converter](https://www.ferntool.com/convert/square-meters-to-square-feet)
- [What is IPv6?](https://www.ferntool.com/what-is-ipv6)
- [How to find your IP address (every device)](https://www.ferntool.com/how-to-find-my-ip-address)
- [Public vs private IP address](https://www.ferntool.com/public-vs-private-ip)
- [What is CGNAT (carrier-grade NAT)?](https://www.ferntool.com/what-is-cgnat)
- [How to hide your IP address](https://www.ferntool.com/how-to-hide-my-ip)
- [How to find your PS5 IP address](https://www.ferntool.com/how-to-find-ip-address-on-ps5)
- [How to find your Xbox IP address](https://www.ferntool.com/how-to-find-ip-address-on-xbox)
- [How to find your smart TV’s IP address](https://www.ferntool.com/how-to-find-ip-address-on-smart-tv)
- [How to find your router’s IP address](https://www.ferntool.com/how-to-find-router-ip-address)
- [What is a good internet speed?](https://www.ferntool.com/what-is-a-good-internet-speed)
- [Why is my internet slow at night?](https://www.ferntool.com/why-is-my-internet-slow-at-night)
- [How to change DNS on Windows 11 and 10](https://www.ferntool.com/how-to-change-dns-on-windows)
- [How to change DNS on a Mac](https://www.ferntool.com/how-to-change-dns-on-mac)
- [How to change DNS on your router](https://www.ferntool.com/how-to-change-dns-on-router)
- [Public DNS servers compared](https://www.ferntool.com/best-public-dns-servers)
- [Why port forwarding isn’t working](https://www.ferntool.com/port-forwarding-not-working)
- [Keeping your internet on during load-shedding](https://www.ferntool.com/internet-during-load-shedding)
- [Fibre vs LTE vs 5G in South Africa](https://www.ferntool.com/fibre-vs-lte-vs-5g-south-africa)
- [How to check if a port is open](https://www.ferntool.com/how-to-check-if-a-port-is-open)
- [How to create a strong password](https://www.ferntool.com/how-to-create-a-strong-password)
- [What is a user agent?](https://www.ferntool.com/what-is-a-user-agent)
- [How to find your MAC address](https://www.ferntool.com/how-to-find-mac-address)
- [What is a good ping?](https://www.ferntool.com/what-is-a-good-ping)
- [Subnet mask cheat sheet (CIDR table)](https://www.ferntool.com/subnet-mask-cheat-sheet)
- [How to find who owns an IP address](https://www.ferntool.com/how-to-find-who-owns-an-ip-address)
- [How to find who owns a domain](https://www.ferntool.com/how-to-find-who-owns-a-domain)
- [How to flush your DNS cache](https://www.ferntool.com/how-to-flush-dns-cache)
- [How to check if an IP address is a VPN](https://www.ferntool.com/how-to-check-if-an-ip-is-a-vpn)
- [What is an ASN (autonomous system number)?](https://www.ferntool.com/what-is-an-asn)
- [How to fix DNS_PROBE_FINISHED_NXDOMAIN](https://www.ferntool.com/how-to-fix-dns-probe-finished-nxdomain)
- [How to set up DMARC (step by step)](https://www.ferntool.com/how-to-set-up-dmarc)
- [Why are my emails going to spam?](https://www.ferntool.com/why-are-my-emails-going-to-spam)
- [How to spot WhatsApp and SMS scams](https://www.ferntool.com/how-to-spot-whatsapp-and-sms-scams)
- [How to fix SPF “too many DNS lookups”](https://www.ferntool.com/spf-too-many-dns-lookups)
- [What to do if you’ve been scammed (South Africa)](https://www.ferntool.com/what-to-do-if-you-have-been-scammed)
- [How to view full email headers](https://www.ferntool.com/how-to-view-email-headers)
- [How to tell if an email is fake](https://www.ferntool.com/how-to-tell-if-an-email-is-fake)
- [What is CIDR notation?](https://www.ferntool.com/what-is-cidr-notation)
- [IPv6 subnet cheat sheet (prefix chart)](https://www.ferntool.com/ipv6-subnet-cheat-sheet)
- [South African ISPs: ASNs, CGNAT, IPs](https://www.ferntool.com/isp/)
- [Vodacom IP address & ASN](https://www.ferntool.com/isp/vodacom)
- [MTN IP address & ASN](https://www.ferntool.com/isp/mtn)
- [Telkom IP address & ASN](https://www.ferntool.com/isp/telkom)
- [Cell C IP address & ASN](https://www.ferntool.com/isp/cell-c)
- [Rain IP address & ASN](https://www.ferntool.com/isp/rain)
- [Afrihost IP address & ASN](https://www.ferntool.com/isp/afrihost)
- [Cool Ideas IP address & ASN](https://www.ferntool.com/isp/cool-ideas)
- [Vumatel IP address & ASN](https://www.ferntool.com/isp/vumatel)
- [Openserve IP address & ASN](https://www.ferntool.com/isp/openserve)
- [Webafrica IP address & ASN](https://www.ferntool.com/isp/webafrica)
- [What is an IP address (guide)](https://www.ferntool.com/what-is-my-ip-address)
- [API docs](https://www.ferntool.com/api)