Hex dump viewer
Hello World! becomes one dump line starting at offset 00000000, with its 12 bytes in hex and the readable text in a side column, then a closing 0000000c. Choose 8 or 16 bytes per line, or paste a dump to recover the bytes. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Text
- Hello World!
- Calculation mode
- Encode
- Hex
- 48656c6c6f20576f726c6421
- Ascii
- Hello World!
- Bytes
- 12
A hex dump is the standard way engineers inspect raw bytes: each line shows a starting offset, a column of two-digit hex values, and a gutter of printable ASCII so patterns jump out without a binary editor. This hex dump viewer builds that layout from plain UTF-8 text or from raw hex digits, and it can parse a dump back into a continuous byte string while rejecting malformed rows instead of silently inventing data. Width is eight or sixteen bytes per line so samples match classic hexdump -C style or a narrower classroom strip.
Encode text or hex into a canonical dump
Optional width selects eight or sixteen bytes per line; sixteen is the default and matches the familiar hexdump -C double column of eight plus eight. Each data line begins with an eight-digit lowercase hexadecimal offset, then spaced byte pairs with a double space between the two half-rows, then a pipe-delimited ASCII gutter where bytes outside printable ASCII appear as dots. A final bare offset line equal to the total length closes the dump the same way classic tools do, so pasted samples line up with shell output students already know.
Identical inputs always produce identical dumps because the path is pure arithmetic with no network, no random salt, and no wall clock. Use encode whenever you need a paste-safe, reviewable view of a short configuration blob, a protocol sample, or a firmware fragment that must be compared byte-for-byte across tickets and tools.
Parse dumps back to bytes and reject bad rows
Set mode to decode and put a multi-line hex dump in text. The parser accepts canonical offset-plus-hex-plus-gutter rows and is tolerant of a colon after the offset and of grouped four-digit hex tokens common in xxd-style pastes. Empty lines and a trailing bare offset marker are ignored.
For every data row the engine checks that the offset continues from the previous row when offsets are present in sequence; a jump, a non-hex token in the byte columns, or a line that cannot be recognized at all is recorded as a malformed dump row. Prefer this capability when search intent is literally hex dump viewer, hexdump online, or parse hex dump with offsets; compact text-to-hex without offsets belongs to the separate text-to-hex converter landing.
FAQ
How do I create a hex dump from text?
The dump field contains offsets, hex columns, and an ASCII gutter; set width to 8 or 16.
How do I parse a hex dump back to bytes?
Send mode decode and put the multi-line dump in text.
What counts as a malformed dump row?
An unrecognized line, non-hex tokens in the byte columns, or an offset that does not continue from the previous data row. The error names the line number and reason and is not billed.
Is the hex dump viewer free?
The browser tool runs free on your device.
What is the difference from a plain text-to-hex converter?
This tool produces and parses classic multi-line dumps with offsets and an ASCII gutter. Compact single-string hex without offsets is a different search intent served by the text-to-hex converter.
Related tools
For developers — API access
Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.
API endpoint
Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, by email and from Telegram — and soon from our app too.
Call it from your stack
curl -X POST https://api.kit.forhosting.com/enc/hexdump \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"text":"Hello World!"}'const res = await fetch("https://api.kit.forhosting.com/enc/hexdump", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"text": "Hello World!"
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/enc/hexdump",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"text": "Hello World!"
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/enc/hexdump", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"text":"Hello World!"}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"text":"Hello World!"}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/enc/hexdump", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"text": "Hello World!"
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "enc.hexdump",
"status": "queued",
"_links": {
"result": "/tasks/tsk_…/result"
}
}The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.
Pricing
Published price — no tokens, no invented credits. A failed task is never charged.
Errors
| HTTP | Code | Meaning |
|---|---|---|
401 | unauthorized | Missing or invalid API key. |
402 | insufficient_balance | Your balance doesn't cover the task price. |
404 | unknown_type | That task type doesn't exist. |
429 | rate_limited | Too many requests. Use the webhook instead of polling. |
Technical notes
Encode text or hex into a canonical dump
Send a JSON body with the required string field text set to the payload you want to inspect, leave mode at encode or set mode to encode explicitly, and choose input_format text when the payload is human-readable Unicode or input_format hex when you already hold raw hex digits with optional spaces, colons, dashes, or zero-x prefixes. The engine serializes text through UTF-8 so multi-byte characters expand correctly, or it normalizes the hex string into an ordered byte array and rejects odd-length digit runs with invalid_input. The response echoes mode, dump, continuous lowercase hex, a best-effort ascii reconstruction, byte length, width, line count, input_format, and an empty malformed_rows array on success.
Parse dumps back to bytes and reject bad rows
Validation failures are not charged on the prepaid API, so probing a truncated or hand-edited dump is safe.
API usage, pricing, workflows, and practical limits
Call the free in-browser hex dump viewer for classroom demos, support playbooks, reverse-engineering notes, and one-off inspections without installing xxd, hexdump, or language-specific helpers. Authors shipping SDKs can map the dump field into a monospace pre block and the hex field into a copy button, while width and lines labels make OpenAPI examples self-explanatory for readers comparing dump formats side by side. Use the prepaid KIT API when a backend, serverless function, firmware test harness, or SDK needs the same encode or decode step under balance at $0.002 per successful item; failed validation never consumes balance after the engine rejects the request. A typical workflow encodes a short configuration token with input_format text and width sixteen for a ticket attachment, then decodes the same paste on the receiving service with mode decode and asserts that hex and bytes match the original length. Another workflow starts from a packet hex field with input_format hex, dumps it for a design review, and keeps the continuous hex field for machine consumers that do not want the gutter. Pair this endpoint with Base64 or URL encoding tools when a payload must survive multiple text-only channels, but keep the steps separate so each landing page matches a single search intent.
Integration use cases
Protocol samples and support tickets
Dump short UTF-8 messages or hex payloads with offsets and an ASCII gutter for tickets and packet notes, then parse the same paste back to continuous hex on the receiving side.
Docs and CI golden checks
Pin encode and decode fixtures—including one malformed-row error—so documentation samples and continuous-integration tests fail fast if dump formatting ever drifts.
Education and reverse engineering
Students and analysts view classic hexdump-style layout in the free browser widget and practice reading offsets, byte columns, and the printable ASCII gutter without local tools.