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Browse all toolsTry BMI Calculator
Pregnancy Week CalculatorRGB to CMYKImage ResizerCM to Inches ConverterHash GeneratorSales Tax CalculatorTarget Heart Rate CalculatorCMYK to HEX
BMI
23.4
Loan EMI
$842/mo
Age
27y 4m
USD → EUR
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Most used tools
Recently added tools. Switch a tab to see the newest in that category.
40w
Pregnancy Week Calculator
Due date, how many weeks pregnant, and baby growth week by week from your last period.
CMYK
RGB to CMYK
Convert RGB color values to CMYK percentages. Free in your browser.
PX
Image Resizer
Resize image online free. Change width and height in your browser.
cm
CM to Inches Converter
Convert centimeters to inches, or inches back to centimeters.
MD5
Hash Generator
MD5 and SHA-256 hash generator. Checksums in your browser. No upload.
TAX
Sales Tax Calculator
Add or remove sales tax from a price. Free sales tax calculator online.
HR
Target Heart Rate Calculator
Target heart rate zones from age using 220 minus age. Free in your browser.
HEX
CMYK to HEX
Convert CMYK percentages to a HEX color code. Free in your browser.
Why SmartToolX
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Every calculation runs in your browser. No server delay and no waiting.
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Free, no account required, no paywalled results.
111+
Tools across health, finance, text, files, and conversion. We add more each week.