Tools
71 free networking tools that run entirely in your browser — nothing is uploaded to a server. Subnet math, DNS lookups, converters, and more.
🧮 IP & Subnet Tools
Calculate subnets, convert addresses, and inspect IP ranges.
- Subnet Calculator (IPv4)Calculate the network, broadcast, host range, netmask, wildcard, and usable hosts for any IPv4 subnet.
- CIDR to IP RangeConvert a CIDR block into its first and last IP address and total address count.
- IP Range to CIDRConvert a start and end IP address into the smallest list of CIDR blocks that covers it.
- Subnet Mask ConverterConvert between CIDR prefix, dotted-decimal netmask, and wildcard mask.
- IP Address to BinaryConvert an IPv4 address to its 32-bit binary form, and back.
- IP Address to IntegerConvert an IPv4 address to a single 32-bit integer, and back.
- Hosts per Subnet TableA quick reference of addresses and usable hosts for every IPv4 prefix length.
- IP Class & Type CheckerIdentify the class (A/B/C/D/E) and type (public, private, reserved) of any IPv4 address.
- Public or Private IP CheckerInstantly tell whether an IPv4 address is public, private, loopback, link-local, or reserved.
- IPv6 Expander & CompressorExpand an IPv6 address to its full form, or compress it with :: notation.
- IPv4 to IPv6 ConverterConvert an IPv4 address into IPv4-mapped IPv6 and 6to4 notation.
- Random IP GeneratorGenerate random IPv4 addresses for testing and examples.
- IP-in-CIDR CheckerCheck whether an IPv4 address falls inside a given CIDR range.
- IPv6 to IPv4 ConverterExtract the embedded IPv4 address from an IPv4-mapped, 6to4, or NAT64 IPv6 address.
- IPv6 Subnet CalculatorCalculate the network, first/last address, and subnet counts for an IPv6 prefix.
- Subnet SplitterSplit a network into a number of equal-sized subnets.
- CIDR AggregatorMerge a list of IPs and CIDR blocks into the smallest set of CIDRs.
- IP Address SorterSort a list of IPv4 addresses in true numeric order, with optional de-duplication.
🔍 DNS & Lookup Tools
Query DNS records, reverse-DNS, geolocation, and registration data — live in your browser.
- DNS Lookup ToolLook up A, AAAA, CNAME, MX, TXT, and NS records for any domain, live via DNS-over-HTTPS.
- Reverse DNS (PTR) LookupFind the hostname (PTR record) associated with an IPv4 or IPv6 address.
- IP Geolocation LookupLook up the approximate location, ISP, and ASN of any IP address.
- MX Record LookupFind the mail servers (MX records) for any domain.
- TXT Record LookupRetrieve the TXT records for any domain.
- SPF Record CheckerFind and display the SPF record for a domain's email authentication.
- DMARC Record CheckerLook up a domain's DMARC policy record for email security.
- NS (Nameserver) LookupFind the authoritative nameservers for any domain.
- Whois / RDAP LookupLook up registration data for an IP address or domain using RDAP.
- All DNS Records LookupQuery A, AAAA, CNAME, MX, TXT, NS, SOA, and CAA records for a domain at once.
- DNS Propagation CheckerCompare a domain's A record across multiple public DNS resolvers.
📡 Network Utilities
Latency tests, reference lookups, and browser/device inspectors.
- HTTP Ping (Latency Test)Measure the round-trip time to a website over HTTPS — the browser's equivalent of a ping.
- Common Port Number LookupSearch a reference of common TCP/UDP port numbers and the services that use them.
- HTTP Status Code LookupLook up the meaning of any HTTP status code, from 200 to 500.
- MAC Address FormatterReformat and validate a MAC address into colon, hyphen, and Cisco dot notation.
- Random MAC Address GeneratorGenerate random, locally-administered MAC addresses for testing.
- User Agent ParserParse a browser user-agent string into browser, OS, and device details.
- My Browser & Device InfoSee everything your browser reveals: user agent, screen, time zone, CPU, and more.
- MAC Vendor LookupLook up the manufacturer of a network device from its MAC address (OUI).
- URL ParserBreak a URL into its scheme, host, port, path, query, and fragment.
- Email Address ValidatorCheck whether an email address has a valid format and see its parts.
🔄 Encoders & Converters
Base64, URL, hex, hashing, JWT, JSON, and more.
- Base64 Encode / DecodeEncode text to Base64 or decode Base64 back to text (Unicode-safe).
- URL Encode / DecodePercent-encode text for URLs or decode percent-encoded strings.
- HTML Entity Encode / DecodeEscape text to HTML entities or decode entities back to characters.
- Text to Hex ConverterConvert text to hexadecimal bytes and back.
- Text to Binary ConverterConvert text to 8-bit binary and back.
- Number Base ConverterConvert a number between binary, octal, decimal, and hexadecimal.
- Hash Generator (SHA)Generate SHA-1, SHA-256, SHA-384, or SHA-512 hashes of any text.
- UUID GeneratorGenerate random version-4 UUIDs.
- JWT DecoderDecode a JSON Web Token's header and payload (no verification).
- JSON Formatter & ValidatorPretty-print, minify, and validate JSON.
- Query String ParserParse a URL query string into a readable table of parameters.
- Punycode / IDN ConverterConvert internationalized domain names to and from Punycode.
- Text Case ConverterConvert text between UPPER, lower, Title, Sentence, camelCase, snake_case, and kebab-case.
- HMAC GeneratorGenerate an HMAC signature from a message and secret key.
- Base32 Encode / DecodeEncode text to Base32 or decode Base32 back to text (RFC 4648).
- ROT13 / Caesar CipherApply a ROT13 or Caesar-shift cipher to text.
- Regex TesterTest a regular expression against sample text and see the matches.
- Text Diff CheckerCompare two blocks of text line by line and highlight what changed.
- JSON to CSV ConverterConvert a JSON array of objects into CSV.
- CSV to JSON ConverterConvert CSV with a header row into a JSON array of objects.
⚙️ Generators & Calculators
Passwords, UUIDs, bandwidth math, unit and timestamp conversion.
- Password GeneratorGenerate strong, random passwords with configurable length and character sets.
- Random String GeneratorGenerate random alphanumeric strings and tokens of any length.
- Download Time CalculatorEstimate how long a download will take for a given file size and connection speed.
- Data Unit ConverterConvert between bits, bytes, KB, MB, GB, and the binary KiB/MiB/GiB units.
- Unix Timestamp ConverterConvert between Unix timestamps and human-readable dates.
- Color Converter (HEX / RGB / HSL)Convert a color between HEX, RGB, and HSL notation.
- Random IPv6 GeneratorGenerate random IPv6 addresses for testing and examples.
- Word & Character CounterCount words, characters, lines, and sentences in your text, live as you type.
- Slugify (URL Slug Generator)Turn any title or phrase into a clean, URL-friendly slug.
- Lorem Ipsum GeneratorGenerate placeholder Lorem Ipsum paragraphs for mockups and design.
- Unix Permissions (chmod) CalculatorConvert between octal (755) and symbolic (rwxr-xr-x) file permissions.
- Password Strength CheckerEstimate the entropy and strength of a password, entirely in your browser.