Free utilities · Run in your browser

Developer tools, built for the way you work.

A focused set of utilities for the daily work of building, debugging, and shipping. Every tool runs entirely in your browser — your input never touches our servers.

Tools available

0 ms

Server roundtrips

MIT

Open source

v0.2

Updated · May 2026

⌘K

Encoding & Decoding

04 · Tools

01 / FMTJSON FormatterFormat, validate, and minify JSON with syntax highlighting.02 / SECJWT DecoderInspect header, payload, and signature of any JWT.03 / ENCBase64 EncoderTwo-way Base64 conversion for strings and files.04 / ENCURL EncoderPercent-encode and decode URL components.

Generators

03 · Tools

05 / GENUUID GeneratorGenerate v4 and v7 UUIDs in bulk.06 / GENHash GeneratorSHA-1, SHA-256, SHA-384, SHA-512 from text or files.07 / GENPassword GeneratorCryptographically secure passwords and passphrases.

Converters

04 · Tools

09 / CVTTimestamp ConverterUnix epoch ↔ ISO 8601 ↔ human-readable dates.10 / CVTYAML ↔ JSONTwo-way conversion between YAML and JSON.

11 / CVTCron BuilderVisual cron expression builder with plain-English readout.SOON

12 / CVTCSV ↔ JSONConvert tabular data between CSV and JSON arrays.

Network & Infrastructure

05 · Tools

13 / NETIP LookupGeolocation, ASN, and ISP info for any IPv4 or IPv6.SOON

14 / NETDNS LookupQuery A, AAAA, MX, TXT, NS, CNAME records.SOON

15 / NETCIDR CalculatorSubnet ranges, host counts, and netmasks from CIDR.

16 / NETSSL CheckerCertificate chain, expiry, and TLS configuration analysis.SOON

17 / NETHTTP HeadersInspect request and response headers for any URL.SOON

Text Tools

03 · Tools

18 / TXTRegex TesterTest regular expressions with live matches and explanations.SOON

19 / TXTDiff ViewerSide-by-side comparison with line and word-level diffs.20 / TXTCase ConvertercamelCase, snake_case, kebab-case, PascalCase, and more.

Cloud Calculators

03 · Tools · NimbusNexus-specific

21 / CLDCloud Cost CalculatorCompare NimbusNexus, AWS, Azure, and GCP costs for your workload.SOON

22 / CLDSLA / Uptime CalculatorTranslate "99.95%" into actual minutes of downtime per year.

23 / CLDRegion Latency TestMeasure latency to all NimbusNexus regions from your browser.SOON

Hosted services

01 · Runs on our servers

24 / SVCInboxesDisposable email addresses for testing signup, invite and password-reset flows. Hosted — unlike the tools above, this one runs on our servers.FREE TIER

PRIVACY

Every tool on this page runs client-side — no server roundtrips, no logging, no telemetry. Open your browser network tab while using any tool to verify there are no outbound requests for your data. The one exception is listed separately under Hosted services and is labelled as such: it is a product that runs on our servers, not a tool that runs in your browser.

Beyond the toolbox

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