CSS Code Editor
Paste a Squarespace custom code block or a plain CSS snippet and see it rendered before you touch anything. Edit text, image URLs and buttons, or every CSS declaration, then copy the finished code straight back.
Edit Custom CSSFREE BROWSER TOOLS
Small browser tools for people who build websites.
Edit a section. Fix an image. Clean up code. Calculate a ratio. CardKit gives you focused tools for common website tasks without accounts, dashboards or complicated setup.
No signup · Browser-based · Built for practical website work
CSS Code Editor · paste, render, copy back
Do one job. Do it quickly.
Each CardKit tool is designed around a single practical task. Open the tool, make the change, export the result and continue working.
Image Canvas Padder
Add clean space around an image and prepare it for square, portrait or landscape layouts without awkward cropping.
Open Image PadderImage Resizer
Resize an image to exact pixel dimensions while keeping control of its proportions and output.
Resize an ImageAspect Ratio Calculator
Convert dimensions, preserve proportions and quickly calculate matching width or height values.
Calculate a RatioHTML Cleaner
Clean and format HTML snippets before pasting them back into a website, template or code block.
Clean HTMLTools should remove work, not create more of it.
Many small website changes do not need a complete design platform or development environment. Sometimes you only need to replace an image, adjust a section, resize a file or clean up a block of HTML. CardKit focuses on those small jobs.
No account
Open the tool and start working.
Focused workflows
Each tool solves one specific problem instead of trying to become another website builder.
Browser-based
Most processing happens directly in your browser.
Easy to leave
Copy or export your result and take it back to the platform you already use.
Built for practical website work
CardKit is useful for:
- Website template buyers
- Etsy digital-product customers
- Squarespace users
- HTML template users
- Freelance designers
- No-code creators
- Small business owners
- People making occasional website edits
You do not need to be a developer to make a small, controlled change.
A simple workflow
01
Bring in what you need
Paste code, open an image or enter your dimensions.
02
Make one controlled change
Use the visual controls instead of searching through a complicated interface.
03
Check the result
Preview the output before you use it.
04
Take it back
Copy, download or export the result and continue working in your original platform.
Your work should stay yours.
CardKit is designed to keep unnecessary data handling to a minimum. Tools that can run locally in the browser do so whenever practical.
For example, the CSS Code Editor processes the HTML you paste inside your browser and does not send that code to CardKit servers. Some previews may still request external resources referenced by the code, such as images, fonts or third-party libraries.
Learn the workflow, not just the tool
CardKit guides explain common website-editing tasks in plain language, including what to change, what not to touch and when a small browser tool is enough.
How to Edit an HTML Template Without Breaking the Layout
Learn how to isolate a section, make controlled changes and avoid accidentally changing the rest of the page.
How to Change Text, Images and Links in an HTML Template
A practical guide to the three edits template buyers make most often.
How to Edit Squarespace Custom Code More Safely
A workflow for making small content changes inside custom HTML sections without rebuilding them.
A Practical Etsy Listing Image Workflow
Prepare consistent product images for digital-product listings using reusable image dimensions and canvas ratios.
FREQUENTLY ASKED QUESTIONS
Is CardKit free?
Yes. The core tools on CardKit are available to use without creating an account.
Do I need to install anything?
No. CardKit tools run in a modern web browser.
Does CardKit upload my HTML?
The CSS Code Editor processes pasted HTML locally in your browser and does not upload that code to CardKit servers.
External resources referenced by the code, such as images, fonts or libraries, may still be requested from their original providers.
Is CardKit only for Etsy templates?
No. Etsy template buyers are one common use case, but CardKit is designed for website templates, custom HTML, Squarespace code sections and other practical web-editing workflows.
Is CardKit affiliated with Etsy or Squarespace?
No. CardKit is an independent product.
Can CardKit fix every website?
No. These are focused utilities, not a full website development environment. Always keep a backup of your original files or code before making changes.
Start with the small job in front of you.
Choose a tool, make the change and get back to your project.