Subnet / CIDR Calculator

Network address, broadcast, mask, and usable host range from an IP + CIDR.

IPv4 Range Expander

Expand a CIDR block or IP range into every address in it.

Random Port Generator

Generate random TCP/UDP ports, optionally avoiding well-known ones.

MAC Address Generator

Generate random, locally-administered MAC addresses.

WebSocket Tester

Connect to a ws:// or wss:// endpoint and exchange test messages.

CIDR Overlap Checker

Paste a list of CIDR blocks and find any that overlap.

MTU Calculator

Effective MTU after common tunnel/encapsulation overhead.

VLAN Calculator

Validate and expand VLAN IDs/ranges, flag reserved and default VLANs.

IPv6 Subnet Calculator

Network range, host count, and compressed/full address forms for an IPv6 CIDR.

Password Generator

Cryptographically random passwords, generated in your browser.

JWT Parser

Decode a JWT's header and payload — no signature check.

SSH Key Fingerprint Generator

SHA256 and MD5 fingerprints for a pasted SSH public key.

Certificate Decoder

Decode a PEM certificate or CSR — subject, SANs, validity, algorithms.

Hash Identifier

Guess a hash's algorithm from its length and format.

SDDL / SID Decoder

Decode an SDDL security descriptor or SID into readable form.

authorized_keys Parser

Parse authorized_keys — type, fingerprint, options, and comment per line.

Entropy Calculator

Shannon entropy of a string, in bits per character and total.

AWS IAM Policy Visualizer & Linter

Readable view of an IAM policy's statements, plus a permissiveness check.

JWK Viewer

Inspect a JWK or JWKS JSON — key type, use, algorithm, and key material.

GCP IAM Policy Formatter

Readable view of a GCP IAM policy's bindings, plus a permissiveness check.

Windows Privilege Decoder

Decode Windows privilege names (whoami /priv) and flag high-risk ones.

GPP Password Decoder

Decrypt a Group Policy Preferences cpassword — for finding and fixing exposure.

JWT Signer

Sign a header/payload as an HS256 JWT using a test secret, via Web Crypto.

Certificate Chain Analyzer

Link pasted PEM certificates into a chain, check each one's validity window.

CSR Generator

Generate an RSA keypair and a PKCS#10 CSR, entirely in your browser.

Generic PEM Inspector

Decode any PEM block — label, byte length, SHA-256 hash, hex dump.

Sigma Rule Validator

Check a Sigma detection rule's required fields and condition references.

bcrypt Hash Generator & Verifier

Generate and verify bcrypt password hashes, entirely in your browser.

Encode / Decode / Hash

Base64, URL encoding, and SHA-1/256/384/512 hashing.

Unix Timestamp Converter

Timestamp to date-time and back, with a live clock.

PowerShell Base64 Decoder

Decode/encode PowerShell -EncodedCommand Base64 blobs.

Windows FILETIME Converter

Convert a 64-bit Windows FILETIME to a date, and back.

GUID Format Converter

Convert a GUID between hyphenated, braced, and bare formats.

AWS Cron Converter

Convert between standard 5-field cron and AWS EventBridge's 6-field syntax.

Wildcard Mask Converter

Convert between subnet masks and Cisco ACL wildcard masks.

Base32 Encode / Decode

RFC 4648 Base32 encode and decode, the alphabet behind TOTP secrets.

Data Format Converter (JSON/YAML/TOML/CSV)

JSON Formatter / Validator

Pretty-print, minify, and validate JSON with clear errors.

Regex Tester

Test a regex against sample text with live match highlighting.

Cron Expression Parser

Human-readable schedule, plus the next 5 run times.

Log Viewer / Filter

Filter pasted logs live by substring or /regex/.

Diff Viewer

Line-level diff between two blocks of text.

List Tools

Sort, dedupe, trim, and prefix/suffix a list of lines.

URL Parser

Break a URL into protocol, host, path, query, and fragment.

User-Agent Parser

Decode a User-Agent into browser, engine, OS, and device.

HTTP Status Code Reference

Searchable lookup for every 1xx-5xx status code.

Windows Event ID Lookup

Searchable reference for common Windows Event IDs.

JSON Diff

Structural diff between two JSON documents, by path.

UUID Batch Generator

Generate one or more random (v4) UUIDs.

Semantic Version Comparer

Compare two semantic versions and see why one outranks the other.

ARN Parser

Decode an AWS ARN into partition, service, region, and resource.

XML Formatter

Pretty-print, minify, and validate XML.

LDAP Filter Builder

Build an RFC 4515 LDAP search filter from attribute/operator/value rows.

Crontab Validator

Validate a full crontab file — schedules, @shortcuts, env vars, comments.

INI Parser

Parse INI config text into sections and keys, with a JSON export.

Kubernetes YAML Validator

Structural sanity check for Kubernetes manifests.

YAML Diff

Structural diff between two YAML documents, by path.

Windows Registry Path Parser

Expand a registry hive abbreviation and split a path into components.

TOML Validator

Parse TOML config text and view it as JSON, with clear errors.

CSV Viewer

View CSV/TSV as a table, with TSV and JSON export.

S3 URL Parser

Break an S3 URL (s3://, virtual-hosted, or path-style) into bucket, region, key.

Git Ignore Generator

Combine curated .gitignore templates for common stacks and tools.

Regex Explainer

Break a regex pattern down token by token into plain English.

Patch Viewer

View a unified diff/patch with colorized additions and removals.

Docker Compose Validator

Structural sanity check for a docker-compose.yml.

Azure Resource ID Parser

Break an Azure resource ID into subscription, resource group, provider, type.

GCP Project ID Validator

Check a Google Cloud project ID against GCP's naming rules.

kubeconfig Cleaner

Pick contexts to keep and export a trimmed kubeconfig with just what they need.

kubeconfig Merger

Merge two kubeconfig files into one, deduplicated by name, conflicts flagged.

Helm Values Diff

Merge a base and override values.yaml Helm-style, see what actually changed.

Apache/Nginx Log Analyzer

Parse Apache/Nginx access log lines into a table with a status-code summary.

Syslog Parser

Parse RFC 3164/5424 syslog lines — PRI, facility/severity, message.

JSONPath Tester

Query pasted JSON with a JSONPath expression and see every match.

Kubernetes RBAC Visualizer

See who a Role/RoleBinding pair actually grants access to, and for what.

DNS Zone File Validator

Check a BIND zone file for SOA/NS presence and common record mistakes.

Nginx Config Visualizer

Re-indent an nginx.conf into a clear block structure.

Terraform/HCL Validator

Structural sanity check for Terraform/HCL — balanced braces, block labels, duplicate resources.

Chmod Calculator

Checkboxes, octal, and symbolic notation, in sync.

fstab Validator

Check /etc/fstab lines for field count, types, options, dump/pass.

Sudoers Syntax Validator

Check sudoers syntax — aliases, Defaults lines, and user/host/command rules.

SSH Config Validator

Check ~/.ssh/config — Host blocks and directive names.

systemd Unit Validator

Check a systemd unit file — sections and a few required-field rules.

Duration Calculator

Elapsed time between two moments, or add/subtract a duration from a date.

Business Day Calculator

Count business days between dates, or add N business days, skipping weekends.

Time Zone Comparison

See one moment rendered across multiple time zones side by side.

iptables/nftables Rule Analyzer

Explain iptables-save rules in plain English, one line at a time.

Firewall Rule Conflict Detector

Find iptables rules that can never fire because an earlier rule already decides.

umask Calculator

Resulting permissions from a umask, or the umask needed for target permissions.

systemd Timer (OnCalendar) Explainer

Parse a systemd OnCalendar= expression and preview its next 5 run times.

DNS Lookup

A/AAAA/MX/TXT/NS/CNAME/SOA/PTR records for a domain or IP.

WHOIS Lookup

Registrar and record lookup, following referrals automatically.

SSL Certificate Checker

Issuer, validity window, SANs, and chain trust for a host.

Ping

4 ICMP echo requests to a host, from our server.

Traceroute

Trace the network path to a host, up to 15 hops.

Port Checker

Check one port, or scan ~27 common ports at once.

DNS Blacklist (RBL) Checker

Check an IP against 5 public DNSBL zones in parallel.

HTTP Header Inspector

Status, headers, and timing per hop, following redirects.

DNS Propagation Checker

Compare a DNS answer across 6 major public resolvers.

HSTS Header Validator

Check a site's HSTS header against preload-list criteria.

Bulk DNS Resolver

Look up the same record type for up to 10 hostnames at once.

Reverse DNS Bulk Lookup

Look up the PTR record for up to 10 IP addresses at once.

DNSSEC Validator

Verify a domain's DNSSEC chain of trust with real cryptographic signature checks.

TLS Cipher Compatibility Tester

See exactly which TLS versions and cipher suites a host will negotiate.

OCSP Checker

Check a certificate's live revocation status via its CA's OCSP responder.

Container Registry / Image Inspector

Look up a public container image's manifest, platforms, and config.

CAA Record Checker

Which Certificate Authorities (if any) are authorized to issue for a domain.

NTP Checker

Query an NTP server over UDP and see its reported time, stratum, and your clock offset.

IP ASN / Registry Lookup

Which Autonomous System and BGP prefix an IP address belongs to.

SPF Record Checker

Parse a domain's SPF record and flag misconfigurations.

DKIM Record Checker

Look up a domain + selector's DKIM key, catch revoked ones.

DMARC Record Checker

Parse policy, percentage, and report-to addresses.

Email Health Check

MX, SPF, and DMARC together — one pass/fail summary.

DMARC Aggregate Report Viewer

Open a DMARC aggregate XML report — parsed locally, never uploaded.

Email Header Analyzer

Received chain with hop timing, plus a From/To/Subject/Date summary.

SMTP Banner Tester

Connect to a mail server and see its SMTP banner and EHLO capabilities.

BIMI Checker

Look up and parse a domain's BIMI brand-logo record.

MIME Parser

Break a raw MIME email into its parts — headers and decoded bodies.