n8n 413 Request Entity Too Large

Which layer refused the request

The two n8n rows were produced on n8n 2.41.3 on 30 September 2026, installed from npm on Node 24 and started with NODE_ENV=production. We sent the same 17 MiB JSON body to a Webhook node and to /rest/login. The nginx row comes from the nginx documentation, which states the default and says a larger body returns “413 (Request Entity Too Large)”. We did not run nginx for this page.

What n8n actually did with a 17 MiB body

A Webhook node set to respond immediately, and a 17 MiB JSON body, one mebibyte over the default:

$ curl -s -w ' %{http_code}' -H 'Content-Type: application/json' \
    --data-binary @big.json http://localhost:5678/webhook/big-body
{"code":0,"message":"There was a problem executing the workflow"} 500

Nothing on the caller’s side mentions size. The n8n log does:

PayloadTooLargeError: request entity too large
    at readStream (…/node_modules/raw-body/index.js:163:17)
    …
    at parseRequestBody (…/n8n/src/webhooks/webhook-helpers.ts:1474:17)
Error in handling webhook request POST /webhook/big-body: There was a problem executing the workflow

The same body sent to the REST API (the path the editor uses) got a proper 413 with a one-line HTML body, <pre>Payload Too Large</pre>. A normal-sized request to the same webhook returned {"message":"Workflow was started"} with 200, so the workflow itself was fine all along.

The fixes

Raise n8n’s limit: N8N_PAYLOAD_SIZE_MAX

The value is in MiB, and n8n only reads it at startup. The docs say “The n8n instance needs to be restarted to apply the new setting.” In Docker, recreate the container so the new variable reaches it:

# docker run
-e N8N_PAYLOAD_SIZE_MAX=32

# docker compose (environment: section of the n8n service)
- N8N_PAYLOAD_SIZE_MAX=32

With N8N_PAYLOAD_SIZE_MAX=32, the 17 MiB request that had failed returned {"message":"Workflow was started"} with HTTP 200, and no PayloadTooLargeError appeared in the log.

Raise the proxy’s limit: client_max_body_size

nginx rejects anything over its limit before n8n gets it, so raising n8n alone changes nothing. Per the nginx docs, the directive is client_max_body_size size; with default 1m, valid in http, server and location:

server {
    server_name n8n.example.com;
    client_max_body_size 32m;   # match or exceed N8N_PAYLOAD_SIZE_MAX
    location / {
        proxy_pass http://127.0.0.1:5678;
        # … your existing proxy headers
    }
}

Then nginx -t and reload. The nginx docs add that “browsers cannot correctly display this error”. If the editor shows only a generic failure when saving a large workflow, check the proxy’s error log as well as n8n’s.

Send big files as form-data instead of JSON

If the large part is a file, have the sender post it as multipart form-data. File parts in form-data webhook payloads fall under N8N_FORMDATA_FILE_SIZE_MAX, 200 MiB by default per the docs, not the 16 MiB JSON limit, and the Webhook node hands them to the workflow as binary data. A file base64-encoded inside JSON is about a third larger than the file and counts against the 16 MiB.

$ curl -s -w ' %{http_code}' -F "upload=@file20.bin"     http://localhost:5678/webhook/big-body
{"message":"Workflow was started"} 200

A 20 MiB file, sent as form-data to the same webhook with N8N_PAYLOAD_SIZE_MAX back at its default of 16. It went through, and n8n wrote the file under .n8n/storage/workflows/…/executions/…/binary_data/. The 17 MiB JSON body had failed on the same instance.

Related

If the webhook answers “The requested webhook … is not registered” instead, the size is not the problem. See webhook not registered. If callers are hitting a URL with localhost in it, see why n8n shows a localhost webhook URL. If n8n’s log behind the same proxy also shows a ValidationError about X-Forwarded-For, see the trust proxy error.

Sources and last verified

Reproduced on n8n 2.41.3 on 30 September 2026; every doc quote was read on the same day. If n8n’s docs and this page disagree, n8n wins. Write to support@flowtemplates.app and we will re-verify.

• n8n Docs — Endpoints environment variables (N8N_PAYLOAD_SIZE_MAX, N8N_FORMDATA_FILE_SIZE_MAX) — checked 2026-09-30
• nginx docs — ngx_http_core_module, client_max_body_size — checked 2026-09-30
• n8n source — body-parser.ts (the payloadSizeMax limit applied to request bodies) — checked 2026-09-30