RenderCard - From my blog need to a public OG API

February 15, 2026

How RenderCard started as a personal OG image solution and became a free URL-based API for social preview cards.

RenderCard started with a simple problem.

I needed clean OG images for my blog posts, and I needed them fast.

I did not want to design a new preview card every time I wrote something. I also did not want to depend on heavy tools just to generate one image.

So I built a small internal tool for myself.

Then it hit me. This is not just my problem.

The original need

I just wanted an easy way to generate:

Open Graph images for blog links
Featured images for articles
A consistent style across posts

At first, it was only part of my writing flow. Pass a title, maybe some metadata, generate the image, done.

Even that saved a lot of time.

From internal tool to public API

Once it was working well, I asked myself:

Why keep this inside one project?

So I turned it into a public API where you generate images using just a URL.

Base endpoint:

https://rendercard.vercel.app/api/rendercard

Minimal usage:

https://rendercard.vercel.app/api/rendercard?title=Hello+World

No dashboard. No login. Just hit a URL and get an image back.

What RenderCard supports

I kept things intentionally simple:

title (required)
description (optional)
theme (optional)
accent (optional hex color)
date (optional: ISO or unix ms)

Themes available:

minimal
centered
split
spotlight
bordered
gradient
glass
dark
mono
code

If you pass something unknown, it just ignores it. Unknown themes fall back to minimal.

Why I built it this way

I wanted it to be:

Fast to use
Easy to plug into any stack
Good enough out of the box
Flexible if you want to tweak things

If you can build a URL, you can use it.

That makes it useful for:

OG tags in blog pages
Twitter or X cards
Docs and articles
Landing pages
Internal tools

Tech direction

It is built with:

Next.js
Edge Runtime

Edge made sense because this is request-based and needs to respond quickly from anywhere.

The goal was speed and reliability, not adding complexity.

What it is not

This is not:

A design tool
A no-code builder
A replacement for full design software

It is just a small utility that turns text into a clean preview card.

What comes next

Things I want to improve:

Better typography control
More layout presets based on real usage
Clearer validation for parameters
Maybe presets for blog platforms

I will keep it simple.

Closing

RenderCard started as something I needed for my own workflow.

Now it is something others can use too.

That is usually how the best side projects happen. Solve your own problem first, then share it.

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