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Free Tools for Developers

Handy, no-nonsense utilities you can use right now — no account, no limits. Built by the team behind ContinuumNexus monitoring.

SLA & Uptime Calculator

Convert 99.9%, 99.99% or any SLA into allowed downtime per day, month and year — or work backwards from a budget.

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HTTP Status Codes

Searchable reference of every HTTP status code with plain-English explanations, class by class.

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SSL Certificate Checker

Check any domain's TLS certificate: expiration date, days remaining, issuer and thumbprint — expired certificates included.

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Free API Health Check

Test any endpoint and see its status code, response time and availability in seconds.

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JWT Decoder

Decode a JSON Web Token's header, payload and claims with human-readable expiry — never stored or logged.

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Cron Expression Generator

Build a cron schedule, read it in plain English and preview the next run times.

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Unix Timestamp Converter

Turn epoch seconds or milliseconds into ISO 8601 and readable UTC dates — and back.

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IP Subnet Calculator

Turn an IP and CIDR into network, broadcast, host range, usable hosts and binary — instantly.

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JSON Formatter & Validator

Format, beautify, minify, and validate JSON payloads instantly with syntax checks.

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JSONPath Tester

Evaluate and extract data from JSON payloads using JSONPath expressions online instantly.

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Base64 Encoder / Decoder

Encode text to Base64 or decode it back — UTF-8 safe, with a URL-safe (base64url) option.

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URL Encoder / Decoder

Percent-encode text for URLs and query strings, or decode %-sequences back to readable text.

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