calculators and converters is a collection of web-based tools/converters/calculators that I have developed through the years. Use them like you want (within reason) and if you really like them, let me know.

Color calculators & converters

CMYK conversion
Convert CMYK color → RGB, HSV, XYZ
HTML Color list
List of named HTML colors
RGB conversion
Convert RGB color → CMYK, HSV, XYZ
Websafe Color list
List of websafe colors

Data calculators & converters

Bandwidth convert
Convert Mbps ⇆ KB/s, GB/day, TB/week
Download calculator
Calculate download time from bandwidth & file size
Data size calculator
Calculate file size from bandwidth & time

Finance calculators & converters

EV mileage calculator
How much $ does your EV car use in kWh per year?
Fuel Cost calculator
How much $ does your car fuel cost per year?
Natural Gas calculator
How much $ does your heating gas cost?
Mortgage loan calculator
Calculate monthly payments for a mortgage loan

Music calculators & converters

Convert BPM to Hz, bar length, fractions
Audio delay
Calculate audio delay length in msec
Music Frequency
Convert pitch to musical note and wavelength
Song length
Calculate song length from BPM
Music Scale
Generate scales with frequencies
Tap your tempo
Tap to find the BPM of a song or a heartbeat

Photo calculators & converters

Aspect ratio
Image Width x Height → aspect ratio
Aspect Fit
Fit an image on a screen
Composition Calculator
Focal length, distance, crop factor → image composition
Depth-of-Field Calculator
Aperture, focal length, distance, crop → depth-of-field
DPI calculator
Print Width x Height and dpi → megapixels
Image filesize calculator
Image Width x Height JPG/RAW/PNG → bytes
Light calculator (EV)
Aperture, shutter time, ISO → Exposure Value
Megapixel calculator
Image Width x Height → megapixels
Megapixel Aspects
See megapixels in different aspect ratios

Physics calculators & converters

Acceleration calculator
Convert m/s² into in/s², g
Battery Capacity (Wh)
What does the kWh of a battery mean?
Distance calculator
Speed x time → distance
Exponential growth
Exponential growth / logarithmic decay
Gladwell's 10000 hours
Deliberate practice according to Malcolm Gladwell
Speed converter
m/s ⇆ km/h, mph, mach
tCO2e Calculator
Calculate your carbon footprint in ton C02/year
Frequency Calculator
Hertz -> wavelength, spectrum
Electrical power
Volt x Amp → Watt, kWh, Ah, Joule, calorie
Wavelength Calculator
Wavelength -> Hz, spectrum

Video calculators & converters

Audio file size calculator
Estimate audio file size for (un)compressed audio
Common bitrates
List of common video bitrates (Prores, DV, DCP, MPEG)
DCP file size
Calculate DCP audio and video filesizes
Foot-Lambert Calculator
Foot-Lambert Calculator for luminance of a screen
Screen size
Calculate screen size from diagional and aspect ratio
Video bitrate
Estimate video bitrate based on resolution, fps and bit depth
Frame rate convert
Framerate conversion with ffmpeg and sox
Video file size calculator
Estimate video file size from resolution and duration

Web calculators & converters

Content Security Policy
Create your Content Security Policy header fast!
Redirection check
Is your site redirection correctly configured?
Security Policy Framework check
Is your SPF correctly configured?
HTTPS config check
Is your site correctly configured for HTTPS?
HTML char map
View all special HTML characters «»
Emoji char map
View all special Unicode characters 🥠
HTML encoder
(HTML/URL) Encode text full of àçčéñtš
SEO Performance
Check your site on 10+ performance test sites
URL encoder
URL Encode text full of àçčéñtš

About this site

Development blog
New tools and other announcements
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How grew since 2006 until now
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Privacy statement (GDPR compliant)
Terms & Conditions
Terms & conditions
How to use the tools
Show me how I can use these tools

How could you use these tools?

Recent Blog Posts

How does a flat image fit on a scope screen?
I had to calculate the dimensions of a flat DCP (1920x1080) on a scope (aspect ratio 2.39) cinema screen, and this is a perfect task for the aspect fit calculator. Let’s...
How does an image (aspect) fit on a screen?
When you have an image with a certain aspect ratio (width/height), and you want to show it on a screen with a different aspect ratio, you have 2 simple options: extend with...
The new beats-per-minute calculator
The BPM (beats-per-minute) calculator was up for an update. The calculator is used to calculate the tempo and the duration of audio effects like delay and LFO. The calculator...
Calculate DCP size from movie length and resolution
To calculate the estimated size of a Digital Cinema Package (DCP) for cinema projection, you need to consider the image size and movie length. The DCP size is primarily determined...
Calculate foot-lambert from screen size, projector lumen
In the projection business, there is a unit for ‘how much light is coming from that screen, actually?’. This is called the foot-Lambert or fL. To calculate foot lamberts (fL)...
Video bitrate from image resolution and bit depth
To estimate the video bitrate based on image resolution and framerate, you can use the following formula: Video Bitrate (bits per second) = Image Resolution (pixels) ×...