Text Processing
Lint Markdown against ~15 markdownlint rules plus 2 Chinese-typography rules, with line-located reports and one-click auto-fix of safe issues
markdown-lint-style-checkerDevelopment
Check Markdown for style issues: heading levels, code fences, list consistency, and more (zero-dependency rule engine)
markdown-linterNetwork
Look up the manufacturer of a MAC address from the IEEE OUI database, or reverse-search a company name to list all its OUI blocks — fully offline
mac-oui-vendor-lookupFormat Conversion
Convert GitHub-flavored Markdown into Slack-friendly mrkdwn and flag unsupported constructs
markdown-to-slack-mrkdwnMedia
Convert M4A (MPEG-4 Audio) files to raw AAC format with quality and channel controls
m4a-to-aacMedia
Convert M4A (MPEG-4 Audio) files to OGG Vorbis format with quality and channel controls
m4a-to-oggMath & Numbers
Fit a binary logistic regression model with gradient descent and predict class probabilities
logistic-regression-calculatorMath & Numbers
Compare two independent samples with the nonparametric Mann-Whitney U rank-sum test
mann-whitney-u-test-calculatorMath & Numbers
Calculate the margin of error for a mean or proportion from sample size, confidence level, and variability
margin-of-error-calculatorMath & Numbers
Calculate logarithms with any valid base, with optional log10, log2, and natural-log comparisons
logarithm-calculatorDevelopment
Convert structured service logs into Mermaid or PlantUML sequence diagrams, with optional latency and error annotations
log-sequence-diagram-converterText Processing
Generate formatted Markdown tables from CSV, JSON, or array data with alignment, header styles, width control, and merge hints
markdown-table-generator