Data
Newline Delimited JSON is a data format commonly identified by .ndjson, .jsonl. Use the listed signatures, MIME types, and structure notes to validate files beyond the extension.
7B {SIGNATURE = bytes.fromhex("7b")
OFFSET = 0
def is_ndjson(path: str) -> bool:
with open(path, "rb") as f:
f.seek(OFFSET)
head = f.read(len(SIGNATURE))
return head == SIGNATUREconst SIGNATURE = [0x7b];
const OFFSET = 0;
// bytes: a Uint8Array / Buffer holding the start of the file
export function isNdjson(bytes) {
return SIGNATURE.every((byte, i) => bytes[OFFSET + i] === byte);
}package fileid
import "bytes"
var isndjsonSignature = []byte{0x7b}
const isndjsonOffset = 0
func IsNdjson(b []byte) bool {
end := isndjsonOffset + len(isndjsonSignature)
if len(b) < end {
return false
}
return bytes.Equal(b[isndjsonOffset:end], isndjsonSignature)
}const SIGNATURE: &[u8] = &[0x7b];
const OFFSET: usize = 0;
fn is_ndjson(bytes: &[u8]) -> bool {
bytes.get(OFFSET..OFFSET + SIGNATURE.len()) == Some(SIGNATURE)
}<?php
$signature = "\x7b";
$offset = 0;
function is_ndjson(string $bytes): bool {
global $signature, $offset;
return substr($bytes, $offset, strlen($signature)) === $signature;
}Newline Delimited JSON is used for data exchange, imports, exports, parser testing, and validation workflows. Encoding, delimiters, versions, and container structure often change implementation behavior.
Untrusted input is not safe just because the format was detected. Account for parser exceptions, large files, unexpected encodings, and external references.
11 samples help test leading-byte detection, parser errors, upload limits, and download behavior.
Blue Sky NDJSON is a Newline Delimited JSON sample based on Wikimedia Commons. It can be used to test downloads, parsers, previews, and file type detection.
01-blue-sky.ndjson8d7276a1905675b2c4c3408161571e16d7fdcf3fdbf489cf9210b778e404217aFlower Garden NDJSON is a Newline Delimited JSON sample based on Wikimedia Commons. It can be used to test downloads, parsers, previews, and file type detection.
02-flower-garden.ndjson64a8414758a1c618180e343e7673d20f271e469c8ccbdb129fd552999cf1685aNavy Blue Sky NDJSON is a Newline Delimited JSON sample based on Wikimedia Commons. It can be used to test downloads, parsers, previews, and file type detection.
03-navy-blue-sky.ndjsond667e600fe8e879f57c6718162c6c437506f19545b0dda322ab955cf4b0d469bNature of the Sky NDJSON is a Newline Delimited JSON sample based on Wikimedia Commons. It can be used to test downloads, parsers, previews, and file type detection.
04-nature-sky.ndjson35bb71f13fe7599219a4c6aa2817da266b1b412f2c9e2fb6ba0faa12a2006d83Sky Landscape NDJSON is a Newline Delimited JSON sample based on Wikimedia Commons. It can be used to test downloads, parsers, previews, and file type detection.
05-sky-landscape.ndjson621e500353508a74dc3f718738eae9ee8cffadd7aab152c4d88caeb61ef189efStarry Sky NDJSON is a Newline Delimited JSON sample based on Wikimedia Commons. It can be used to test downloads, parsers, previews, and file type detection.
06-starry-sky.ndjson37c19e64aff8b6b4a91645f79761e28a5007f74a81e381828f1b01a107d9cfc9Blue Night Sky NDJSON is a Newline Delimited JSON sample based on Wikimedia Commons. It can be used to test downloads, parsers, previews, and file type detection.
07-blue-night-sky.ndjson34467b79eee3ed7184243cdf8a764937d213c7809def48448f2e0e24f90d01f2Hibiscus Flower NDJSON is a Newline Delimited JSON sample based on Wikimedia Commons. It can be used to test downloads, parsers, previews, and file type detection.
08-hibiscus-flower.ndjson1d50dcf715c4fe621060ee607ce86518633e0ad2ffcb456d7bf28cea30bb0411Arctic Sky NDJSON is a Newline Delimited JSON sample based on Wikimedia Commons. It can be used to test downloads, parsers, previews, and file type detection.
09-arctic-sky.ndjson041153e643f792c655c8f6312f481bd6570b4b9c8ac73f0263697f9ebf2fc7c3Sunset Rays NDJSON is a Newline Delimited JSON sample based on Wikimedia Commons. It can be used to test downloads, parsers, previews, and file type detection.
10-sunset-rays.ndjson795d3f86a48a48d3cb46d9a65d791673017c54e4b11bdd84f4b5a15889af3b1dNASA Blue Marble NDJSON is a Newline Delimited JSON sample based on NASA Image and Video Library. It can be used to test downloads, parsers, previews, and file type detection.
nasa-blue-marble-2012-east.ndjsone108e76333f8782f2f3d7636a7245b5ee0340132e6057c08e7ec6d28d7b991ccNewline Delimited JSON files begin with the byte signature 7B ("{"). Detect the format by reading these leading bytes rather than trusting the file extension alone.
The MIME type for Newline Delimited JSON is application/x-ndjson, application/jsonl.
Newline Delimited JSON files use the .ndjson, .jsonl extension. The extension is a convention only and does not guarantee the file contents, so combine it with signature and structure checks.