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Flashman has 28 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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Today's pick: portainer env

Did you know? Regex is not magic — it's a tiny parser you write in a notation nobody enjoys.

Popular tools

Most-used utilities by developers visiting Flashman.

json

json · format

base64

base64 · encode

url

url · encode

jwt

jwt · decode

hash

sha256 · sha512

yaml json

yaml · json

markdown

markdown · editor

markdown viewer

markdown · viewer

markdown pdf

markdown · pdf

color

hex · rgb

diff

diff · compare

portainer env

portainer · docker

matlab array

matlab · simulink

matlab struct

matlab · simulink

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New to a topic? These guides explain the concepts and link to the tools.

From the blog

Workflows, debugging tips, and product updates.

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AllEncode / DecodeFormat / BeautifyGenerateConvert / CalcDebugTextMATLAB / Simulink
formatpopular
json
json • format • validate
encodepopular
base64
base64 • encode • decode
encodepopular
url
url • encode • decode
debugpopular
jwt
jwt • decode • generate • sign
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
debugpopular
portainer env
portainer • docker • env • self-hosted
text
case
case • camel • snake • kebab
engineeringpopular
matlab array
matlab • simulink • matrix • array
engineeringpopular
matlab struct
matlab • simulink • struct • parameters