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Flashman has 27 tools. Browse developer utilities for JSON, JWT, encoding, hashing, cron, Markdown, and MATLAB/Simulink workflows—processed locally in your browser. No signup, no uploads.
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Did you know? Pretty-printed JSON is for humans. Minified JSON is for machines. Both are valid life choices.
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Most-used utilities by developers visiting Flashman.
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From the blog
Workflows, debugging tips, and product updates.
- HTTP 429 Retry-After: debug backoff safely
- Base64 padding and URL-safe API bugs
- Review MATLAB structs from JSON before Simulink masks
- JSON enum casing: debug API contract mismatches
- Base64url padding: debug signature integration bugs
- Cron DST backfills: debug production replay windows
formatpopular
json
json • format • validate
encodepopular
base64
base64 • encode • decode
encodepopular
url
url • encode • decode
debugpopular
jwt
jwt • decode • debug
encode
pem key newline
pem • key • newline • env
encode
html entities
html • entities • encode • decode
debugpopular
hash
sha256 • sha512
convertpopular
yaml json
yaml • json • convert
format
sql
sql • format
format
xml
xml • format • minify
format
css
css • beautify • minify
formatpopular
markdown
markdown • editor • preview
formatpopular
markdown viewer
markdown • viewer • render
convertpopular
markdown pdf
markdown • pdf • export
generate
uuid
uuid • generate
generate
password
password • generate
generate
cron
cron • schedule
generate
qr
qr • qrcode • generate
convert
timestamp
unix • iso • convert
convertpopular
color
hex • rgb • contrast
convert
number bases
bin • oct • dec • hex
convert
units
bytes • ms
debug
regex
regex • test
debugpopular
diff
diff • compare
text
case
case • camel • snake • kebab
engineeringpopular
matlab array
matlab • simulink • matrix • array
engineeringpopular
matlab struct
matlab • simulink • struct • parameters