Tools

Outils

Des utilitaires petits, rapides et respectueux de la vie privée. Le catalogue calcule dans votre navigateur et n'envoie rien nulle part ; la seule exception est la salle rouge, où un outil interroge le service officiel qu'il indique, et uniquement lorsque vous appuyez sur « Ask ».

Three floors, one rule. The main floor is the catalogue: every tool with a manifest, golden vectors and a fixed shape, computing in your browser and nowhere else. The green room holds the tools whose form is still finding itself, same privacy, labelled as early. The red room is the one place a tool sends your input out, to the official service named on screen, and only when you press Ask.

Read this page as

Paste what you have

A token, a header block, a log line, a certificate, a CIDR: paste it and the tools that recognise its shape line up, the surest first.

Matched in your browser against each tool's own input patterns; nothing is stored or sent.

By what you need to do

The same index, grouped by the verb: what each tool does to what you give it.

Decode something I have28

Tools that take an artefact as it is, a token, a packet, a header, a string, and show what is inside it.

Understand how something works14

Explainers, references and models: the thing laid out so a decision about it can be made.

Compute or convert30

Arithmetic and conversion with the rules shown: addresses, timings, encodings, sizes.

Build or generate10

Tools that produce something to take away: a command, a policy, a plan, a configuration.

Check, validate or simulate9

Tools that answer yes or no, and show why: validators, graders, testers, comparers and simulators of a system's own order.

Workflows

Five chains that follow one thing from tool to tool. What the first shows is what the next takes. Started here; more arrive as data.

Recently added

The newest tools, from the changelog, newest first.

  • Routing table explainerPaste the output of ip route, netstat -rn or route print to read every route field by field, see which default route wins, and ask which route a destination would use, by longest prefix and then metric.
  • CGN port blocks and MAP port setsDivide one public IPv4 address among subscribers: port blocks per address and per pool (RFC 7768), RFC 7422 deterministic mapping with its forward and reverse lookup, and the MAP-E and MAP-T port set of a PSID (RFC 7597), with the log volume that blocks remove.
  • BFD timer calculatorEnter both systems' BFD intervals and Detect Mult to get, for each direction, the agreed transmit interval, its jitter range, the detection time the receiver computes and whether Echo may run, every number explained with its RFC 5880 section; or paste a BFD Control packet in hex to decode it field by field.
  • Route origin validation calculatorPaste a route (prefix and origin AS) and the VRPs you have, and get its RFC 6811 state (Valid, Invalid or NotFound) with the reason VRP by VRP: which VRPs cover it, which match, and why the others fail. AS 0 and maxLength are handled as the RFCs state them, IPv4 and IPv6 alike, and nothing is fetched.
  • Syslog message parserPaste one syslog message, or a TCP frame carrying one, and read every field named in the order its RFC names them: the PRI opened into facility and severity, the RFC 5424 header, the structured data element by element, the message; or the BSD form of RFC 3164 with its TIMESTAMP, HOSTNAME, TAG and CONTENT. Whatever is non-compliant is said in the RFC's own words. Nothing is sent anywhere.
  • Log level mapperPick a level in one logging system (syslog, the Linux kernel, Cisco IOS, Junos, Windows Event Log, .NET, Python, java.util.logging, Log4j 2, OpenTelemetry) and read its nearest equivalent in every other, with each system's own number and words, where the match is exact and where it is only the nearest rung. The bridge is OpenTelemetry's SeverityNumber, the one scale defined to hold the others. Nothing is sent anywhere.

The general-purpose index

91 general-purpose tools in 11 categories, every one of them listed below; the 96 tools built for a single vendor's platform are in the vendor hubs. Jump to a category, show only some, or switch between cards and the list.

Certificats et PKI

ToolBadgesPostureAnchors
ACME dns-01 TXT computeracme-dns01Certificats et PKInew4 GVcompute / verifyRFC 8555 · RFC 7638 · RFC 4648
Certificate chain buildercert-chain-builderCertificats et PKInew21 GVorder / validate (offline)RFC 5280 · RFC 8446 s4.4.2 · CA/B Forum BR 2.3.1
Décodeur de certificats X.509x509Certificats et PKI7 GVdecode / explainRFC 5280 · RFC 6960 · RFC 7633
Décodeur de CSRcsr-decoderCertificats et PKIdecode / verifyPKCS#10 / RFC 2986 · RFC 5280
Let's Encrypt rate-limit plannerletsencrypt-rate-limitsCertificats et PKInew3 GVcomputeLE Rate Limits · Public Suffix List
Planificateur de renouvellement de certificatcert-renewal-plannerCertificats et PKInew5 GVcalculate / explainCA/Browser Forum SC-081v3 · RFC 5280 · RFC 8555

Encodage et données

ToolBadgesPostureAnchors
ASCII table explorerascii-tableEncodage et donnéesnew19 GVlook up / convert / explainRFC 20 (USAS X3.4-1968) · Unicode 18.0.0 UCD · UAX #44 · UTS #39 · WHATWG HTML · RFC 8259 · RFC 3986 · C11 (N1570) · ECMA-262 · Tcl 8.4
Charset converter and mojibake fixercharset-equivalencyEncodage et donnéesnew35 GVconvert / explain / repairWHATWG Encoding Standard · Unicode 18.0.0 (3.9, 3.10) · RFC 3629 · RFC 2781 · RFC 4648 · Unicode vendor mapping tables (IBM 437, 850, 037, 500)
Codec Base64, Base32, Hex et pourcentbase64Encodage et donnéesencode / decodeRFC 4648 · RFC 3986
Convertisseur de temps UnixepochEncodage et données7 GVconvert-
JSON ↔ YAML Converterjson-yaml-convertEncodage et données16 GVconvertYAML 1.2.2 · RFC 8259
JSON Formatter & Validatorjson-formatterEncodage et données19 GVformat / validateRFC 8259 · ECMA-404 · RFC 6901
Multi-time-zone meeting plannertimezone-meeting-plannerEncodage et données4 GVcompute-
Roman numerals converterroman-numeralsEncodage et données21 GVconvert / explain-
Time calculatortime-calculatorEncodage et données8 GVcompute-
Unicode inspectorunicode-inspectorEncodage et donnéesnew20 GVinspect / revealUnicode 18.0.0 UCD · UTS #39 · UTS #55 · UAX #9 · UAX #44 · RFC 3629 · RFC 2781

Identité et jetons

ToolBadgesPostureAnchors
Décodeur et vérificateur de JWTjwtIdentité et jetonsdecode / verifyRFC 7519 · RFC 7515 · RFC 7518
Décodeur OIDCoidcIdentité et jetons17 GVdecode / explainOpenID Connect Core 1.0 · OpenID Connect Discovery 1.0 · RFC 6749 · RFC 7519
JWKS explainer + key matcherjwks-explainerIdentité et jetons13 GVdecode / explainRFC 7517 · RFC 7518 · RFC 8037
LDAP filter explainerldap-filter-explainerIdentité et jetonsnew14 GVdecode / explainRFC 4515 grammar; anchored errors; AD matching-rule OIDs recognized
OAuth flow chooseroauth-flow-chooserIdentité et jetonsnew12 GVcompute (deterministic)RFC 6749/7636/8252/8628; RFC 9700 retirements encoded
SAML Decodersaml-decoderIdentité et jetons20 GVdecode / explainOASIS SAML 2.0 · W3C XML-DSig · OWASP XXE
TOTP / HOTP Generator & Validatortotp-hotpIdentité et jetonsgenerate / verifyRFC 6238 · RFC 4226
Vérificateur et challenge OAuth PKCEpkceIdentité et jetonsgenerate / verifyRFC 7636 · RFC 6749

Operations & Fieldcraft

ToolBadgesPostureAnchors
Before/After Health Snapshot Comparatorhealth-snapshot-comparatorOperations & Fieldcraftnew13 SVdeclare / gate / export (advisory)Original ruleset (D-18)
Change Blast-Radius Mapperchange-blast-radius-mapperOperations & Fieldcraftnew11 SVmap / assess / export (advisory)Original ruleset (D-18)
Change Window Runbook Builderchange-window-runbook-builderOperations & Fieldcraftnew13 SVstructure / sequence / export (advisory, deterministic rule-firing)Original ruleset (D-18)
chmod permission calculatorchmod-permission-calculatorOperations & Fieldcraftnew25 GVconvert / explainPOSIX.1-2024 chmod · POSIX.1-2024 ls · GNU coreutils 9.11 chmod(1)
Digital transformation trackerdigital-transformation-trackerOperations & Fieldcraftnew14 GVcompute (deterministic)Certainty-tiered milestone dataset; attribution invariant enforced by golden vectors
Fault Hypothesis Builderfault-hypothesis-builderOperations & Fieldcraftnew13 SVstructure / rank / export (advisory, deterministic rule-firing)Original ruleset (D-18)
Flow Path Reasonerflow-path-reasonerOperations & Fieldcraftnew13 SVmodel / rank / export (advisory)Original ruleset (D-18)
Incident Timeline & RCA Builderincident-timeline-rca-builderOperations & Fieldcraftnew12 SVstructure / correlate / export (advisory)Original ruleset (D-18)
Log level mapperlog-level-mapperOperations & Fieldcraftnew18 GVmap / explainRFC 5424 · OpenTelemetry Logs Data Model · Linux printk · Cisco IOS logging · Junos syslog · Windows event manifest levels · .NET LogLevel · Python logging · java.util.logging · Log4j 2
Network operating system comparernetwork-os-comparerOperations & Fieldcraftreference (vendored)Vendor architecture documentation
Packet Capture Plan Builderpacket-capture-plan-builderOperations & Fieldcraftnew13 SVplan / rank / export (advisory)Original ruleset (D-18)
Python playgroundpython-playgroundOperations & Fieldcraftnew54 GVrun (local, WebAssembly)CPython 3.14.2 via Pyodide 314.0.7 (WebAssembly, MPL-2.0) · PEP 3156 asyncio (top-level await)
Syslog message parsersyslog-message-parserOperations & Fieldcraftnew17 GVdecode / explainRFC 5424 · RFC 3164 · RFC 5426 · RFC 6587 · RFC 5425
TAC Escalation Packet Buildertac-escalation-packet-builderOperations & Fieldcraftnew12 SVcollect / structure / export (advisory)Original ruleset (D-18)
Terminal, shell, TTY and console explainerterminal-stack-explainerOperations & FieldcraftexplainPOSIX termios

Réseau

ToolBadgesPostureAnchors
BFD timer calculatorbfd-timersRéseau42 GVcalculate / decodeRFC 5880 s4.1, s6.6, s6.8.2 to s6.8.9 · RFC 5881 s4 · RFC 5883 s3, s5 · RFC 7419 s3
Bits, bytes and throughputbits-bytesRéseaunew22 GVconvertIEC 60027-2 / IEC 80000-13 (NIST) · RFC 2544 App. C · ITU-T V.90 · ITU-T G.704 · IEEE 802.3-2022
Boîte à outils IPv6ipv6Réseau30 GVexpand / compress / explainRFC 4291 · RFC 5952 · RFC 4380 · RFC 4607 · RFC 7346
Cable run plannercable-run-plannerRéseaunew14 GVcompute (deterministic)ANSI/TIA-568 channel limits + IEEE 802.3 optic reaches; rules table pinned by golden vectors incl. exact-at-limit cases
Calculateur CIDR / de sous-réseauxcidrRéseau26 GVcalculate / explainRFC 4632 · RFC 1122 · RFC 3021 · RFC 6890 · IANA IPv4 Special-Purpose Address Space
CGN port blocks and MAP port setscgn-port-blocksRéseaunew36 GVcalculate / reverseRFC 6888 · RFC 7422 · RFC 7768 · RFC 7597 · RFC 7599 · RFC 6269 · RFC 6302 · RFC 6335
DHCP option 43 generatordhcp-option-43Réseau17 GVcomputeRFC 2132 s8.4 · Cisco 97066 · Ruckus KB 000008703 · Ubiquiti 204909754 · Extreme XIQC DG · Aruba AOS · Fortinet FortiAP
dig command builderdig-command-builderRéseaunew39 GVbuild / generate (local)BIND 9 dig manual · RFC 1035 · RFC 3596 · RFC 6891 · RFC 3225 · RFC 4034 · RFC 4035 · RFC 5936 · RFC 1995 · RFC 8482 · RFC 7858 · RFC 8484 · IANA DNS Parameters
dig output explainerdig-output-explainerRéseaunew15 GVdecode / explain (local)RFC 1035 · RFC 6891 · RFC 2308 · RFC 9499 · RFC 8490
HTTP methods comparisonhttp-methods-comparisonRéseaunew19 GVexplainRFC 9110 §9.3 · RFC 10008 (QUERY) · IANA HTTP Method Registry · RFC 5789 (PATCH) · RFC 4918/3253/5323 (WebDAV)
HTTP status code explainerhttp-status-code-explainerRéseaunew12 GVexplainRFC 9110: HTTP Semantics · RFC 6585: Additional HTTP Status Codes · RFC 7725 (451) · RFC 8297 (103 Early Hints)
MTU / MSS calculatormtu-mssRéseau25 GVcalculate / referenceRFC 791/8200/9293/768 (header sizes) · RFC 2784 GRE · RFC 7348 VXLAN · RFC 8926 GENEVE · RFC 2516 PPPoE · RFC 3032 MPLS
nslookup output explainernslookup-output-explainerRéseaunew4 GVdecode / explain (local)RFC 1035 · RFC 2308 · RFC 2782 · RFC 2181 · RFC 9499
OUI / MAC vendor lookupoui-lookupRéseaunew30 GVdecode / lookupIEEE MA-L · RFC 9542 · RFC 1112 · RFC 2464 · RFC 9568
p0f passive TCP/IP signature explainerp0f-signature-explainerRéseaunew10 GVdecode / explainp0f v3
PAC file explainer and validatorpac-file-explainerRéseaunew6 GVparse / validatePAC (FindProxyForURL)
Registered domain (eTLD+1)public-suffixRéseaunew8 GVcomputePublic Suffix List
Route origin validation calculatorrpki-origin-validationRéseaunew40 GVcompute / explainRFC 6811 · RFC 9582 · RFC 6483 · RFC 7607 · RFC 9319 · RFC 8416 · RFC 5396
Routing table explainerrouting-table-explainerRéseaunew18 GVdecode / explain (local)ip-route(8) · ip-rule(8) · rtnetlink(7) · route(8) · FreeBSD netstat(1) · Apple netstat.1 · Microsoft route print · RFC 1812 s5.2.4.3
Syslog PRI decoder + encodersyslog-pri-decoderRéseau17 GVdecode / encodeRFC 5424 · RFC 3164

Security & WAF

ToolBadgesPostureAnchors
CSP evaluatorcsp-evaluatorSecurity & WAFnew19 GVevaluate / gradeCSP Level 3 (W3C)
CVSS vector decodercvss-vector-decoderSecurity & WAFnew10 GVdecode / scoreCVSS v3.1 (FIRST.org)
HTTP header-order fingerprinthttp-header-order-fingerprintSecurity & WAFnew7 GVdecode / explain-
JA3 / JA3N passive TLS fingerprintja3-tls-fingerprintSecurity & WAFnew16 GVcompute (deterministic)-
JA4 / JA3 TLS fingerprint decoderja4-fingerprint-decoderSecurity & WAFnew13 GVdecode / computeJA4 (FoxIO) · JA3 (Salesforce) · BSD 3-Clause
OGNL injection decoderognl-injection-decoderSecurity & WAFdecode / explainCVE-2017-5638 · CVE-2018-11776
PAN-OS policy evaluation orderpanos-policy-evaluation-orderSecurity & WAF14 GVexplainPAN-OS Device Groups · Security Policy Rulebase Best Practices · Defining Policies on Panorama
Secure Headers Analyzersecure-headersSecurity & WAF15 GVanalyze / gradeOWASP Secure Headers Project · RFC 6797 · CSP Level 3 · RFC 6265bis
SSRF URL classifierssrf-url-classifierSecurity & WAFnew113 GVclassify / flagRFC 1918 · RFC 3986 · IANA special-purpose registries · RFC 4291 · RFC 6052 · RFC 4380
User-Agent entropy analyzeruser-agent-entropy-analyzerSecurity & WAFnew8 GVdecode / explain-
XML Decoderxml-decoderSecurity & WAF5 GVdecode / explain (XXE-hardened)W3C XML 1.0 · W3C Namespaces · OWASP XXE

Text & utilities

ToolBadgesPostureAnchors
Cron expression explainercron-expression-explainerText & utilitiesnew23 GVexplaincrontab(5) · POSIX crontab
Expect script explainerexpect-script-explainerText & utilitiesnew22 GVexplain (deterministic)expect(1), Expect version 5 · Tcl 8.4 · ssh_config(5)
Greek alphabet explainergreek-alphabetText & utilities9 GVconvert / explain-
Text DiffdiffText & utilitiescompare / highlight-

Web & HTTP

ToolBadgesPostureAnchors
Color contrast & formatcolor-contrast-formatWeb & HTTPnew15 GVcompute / convertWCAG 2.2 · CSS Color 4
CSS selector testercss-selector-testerWeb & HTTPnew14 GVmatch / explainCSS Selectors 4 · CSS Syntax 3 · HTML Living Standard
CSS specificity calculatorcss-specificity-calculatorWeb & HTTPnew8 GVcompute / explainCSS Selectors 4 · CSS Cascade 5
curl command buildercurl-command-builderWeb & HTTPnew11 GVbuild (deterministic)curl manual · everything curl
curl command explainercurl-command-explainerWeb & HTTPnew10 GVexplain / translatecurl manual · RFC 9110
HTML structure & DOM explainerhtml-structure-explainerWeb & HTTPnew14 GVparse / explainHTML Living Standard · WCAG 2.2
HTTP message decoderhttp-message-decoderWeb & HTTPnew22 GVdecode / explainRFC 9112 · RFC 9110 · RFC 9111 · IANA HTTP registries · rfc6265bis · RFC 7617 · RFC 6648
HTTP request translatorhttp-request-translatorWeb & HTTPnew12 GVtranslateRFC 9112 · RFC 9110
Meta, Open Graph & JSON-LD inspectormeta-og-jsonld-inspectorWeb & HTTPnew14 GVparse / explainHTML Living Standard · Open Graph protocol · JSON-LD 1.1 · RFC 6596 · HTML+RDFa 1.1
Regex ToolkitregexWeb & HTTP24 GVtest / explainECMAScript regular expressions
Sorting Algorithm Steppersorting-algorithm-stepperWeb & HTTPnew12 GVcompute (deterministic)Textbook-canonical sorting variants; correctness enforced by golden vectors + per-run sortedness invariant
URL Inspectorurl-inspectorWeb & HTTP12 GVdecode / explainRFC 3986 · WHATWG URL · RFC 3492

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