I’m currently developing a Shopify store for one of my clients using a custom theme built with theme blocks. Most of the structure/sections is being created directly through theme editor in the homepage ie. index.json template.
While working locally using Shopify CLI (theme pull / push) through GIT, I’m running into the following error when trying to save or push changes:
“Template content exceeds 512 KB limit.”
Because the homepage is heavily built using sections and blocks, the index.json become quite large. As a temporary workaround, I’ve tried minifying the JSON file repeatedly, but that’s not a practical long-term solution.
I wanted to ask:
Is Shopify aware of this 512 KB template limit?
Are there any plans to increase this limit?
Is there a recommended best practice to avoid hitting this limit (besides manual minification)?
Would really appreciate any insights or guidance.
Thank you so much!
Unfortunately, there is little documentation on this. But as the limits on templates after theme block introductions have been changed repeatedly (50 blocks per section is gone), there are just still the block depth limit (about 9) and then the 512kb size.
fortunately, the 512kb size only applies to the dev thing, it seems, as github integration doesn’t seem to block on it, and saving it in the editor works fine.
But to help on the dev side, you can run a simple script that removes all the white space to compress the file quite a bit, and further than that, you could have it remove keys with default data, like a lot of keys have and empty string as the default, so you could filter out all key/value pairs that have a value of empty string.
Would be nice if Shopify just removed any such limits, maybe just warning about the fact crazy configs and depth could result in rendering performance issues, if that is their concern.
Or at least have the editor not save values that match the default…though presumably that is so that changed defaults don’t break existing configs?
thekwoka is right that minifying can buy some room, but Shopify now documents 512 KB as the maximum size of each JSON template file:
The same page currently lists 50 blocks per section, 1,250 blocks per JSON template or section group, and a maximum theme-block nesting depth of 8 levels excluding the section level.
Because Shopify documents 512 KB as a theme file limit, I would not rely on the theme editor or GitHub sync as a supported bypass, even if one of those routes currently accepts the file.
For a long-term fix, I would minify once to measure the real payload, then identify which sections and block settings account for most of the bytes. index.json stores the sections, blocks, order, and their settings, so the durable fix is to store less page content there.
For repeated structured content such as FAQs, cards, slides, or testimonials, a custom theme can give the section a metaobject or metaobject_list setting and loop over those entries in Liquid. The template then stores references while the content fields live in the metaobjects. This only creates a meaningful saving if you remove the equivalent per-item blocks and inline settings.
For layout or content that does not need to be individually edited or reordered, moving more of the fixed structure into the section or a snippet can reduce the template data too.
Minification is still useful as an automated build step for headroom, but I would treat it as a temporary measure rather than the architectural fix. The nesting limit is separate; the amount of serialized block and settings data is what drives the 512 KB file size.