free web tools & calculators

This website contains a bunch of web-based tools (you don't need to install anything, just run them here) that I have developed through the years. Use them like you want (within reason) and if you really like them, let me know.

Recent blog posts

Create a Content-Security Policy: A CSP or Content-Security-Policy is a definition of what kind of external or internal content is allowed in your website.… (1 June 2020)

Calculate audio delay for any tempo (BPM) Calculate exponential growth trends How to convert from Mbps to MB/s How to find and copy/paste emojis 😜 Calculate kWh price for an electric car Check if your site is HTTPS ready HTML Color List update RGB Convert: more color models Megapixel: compare your camera’s resolution

How could you use these tools?

I can write to my USB stick at 13 MB/s. So how much can I write in 15 minutes?
Click on data >> filesize
Fill in 13 MB/s and 15 minutes. This will give you 11.7 GB in those 15 minutes.
Click here for more examples

Calculator tools

Acceleration calculator
Convert m/s² into in/s², g

Distance calculator
Speed x time → distance

Electric Car calculator
How much $ does your electric car use in kWh per year?

Exponential growth
Exponential growth / logarithmic decay

Fuel Cost calculator
How much $ does your car fuel cost per year?

Gladwell's 10000 hours
Deliberate practice according to Malcolm Gladwell

Speed converter
m/s ⇆ km/h, mph, mach

Mortgage loan calculator
Calculate monthly payments for a mortgage loan

Color tools

CMYK conversion

HTML Color list
List of named HTML colors

Pantone Color list
List of named Pantone colors

RGB conversion

Websafe Color list
List of websafe colors

Data tools

Bash boilerplate
Deliberate practice according to Malcolm Gladwell

Bandwidth convert
Mbps ⇆ KB/s, GB/day, TB/week ...

Cloud Storage Cost
Calculate storage cost for AWS, Google, Azure ...

Data size calculator
Calculate 10 Mbps x 6.5 hours = ? GB

Electrical power
Volt x Amp → Watt, kWh, Ah, Joule, calorie

Music tools

Convert BPM to Hz, bar length, fractions

Audio delay
Calculate audio delay length in msec

Song length
Calculate song length from BPM

Tap your tempo
Tap to find the BPM of a song or a heartbeat

Photo tools

Aspect ratio
Image Width x Height → aspect ratio

Composition calc
Focal length, subject distance, crop factor → image composition

Aperture, focal length, subject distance, crop → depth-of-field

DPI calculator
Print Width x Height and dpi → megapixels

Image filesizes
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

Video tools

Audio file size
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

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
Estimate video file size from resolution and duration

Web tools

Content Security Policy
Create your Content Security Policy header fast!

Redirection check
Is your site redirection 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

About this site

Development blog
New tools and other announcements

Remarks about this site? Let me know!

How grew since 2006 until now

Privacy Statement
Privacy statement (GDPR compliant)

Terms & Conditions
Terms & conditions

How to use the tools
Show me how I can use these tools