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OctetBenchBY SMARTFACT

FREE TEXT, HEX AND BYTE EDITOR

Edit a byte and keep the original in reach

Updated

A hex-byte edit replaces a selected byte with an explicit hexadecimal value. OctetBench lets you make that change, undo it and download the complete current byte buffer.

Edit bytes locally →See how it works ↓

Free to use. No account, email address or trial. Your work stays in your browser.

The selected first byte replaced with hexadecimal 42.
A deliberate byte edit changes the buffer; changing a view does not.

Apply the original bytes

Supply exact bytes in hexadecimal and apply them. The checked sequence is 41 C3 A9 0D 0A. Use a small readable buffer before changing a byte.

The original five bytes loaded before editing.
Know the starting value before making a change.

Replace one selected byte

Select the byte and enter hexadecimal 42 as its replacement. Applying the edit changes the buffer, so its text interpretation can change too. This is an explicit edit, not an automatic repair.

The first byte changed from 41 to 42.
Choose the replacement deliberately.

Undo before keeping the result

Undo restores the previous byte change. There are 20 byte-change undo steps. The checked journey undoes the edit before downloading the restored original bytes.

The original first byte restored by Undo.
Verify which state you are about to keep.

Download the current complete buffer

Download creates a new local binary file rather than overwriting your original file. The grid previews 256 bytes, but the export contains the complete current buffer, up to 65,536 bytes. Closing the tab does not retain work automatically.

The restored byte buffer ready for its binary download.
A saved file can outlive the temporary workbench tab.
MADE FOR DEVELOPERS AND INTEGRATORS

For developers, integrators and people checking exact values before using them in another system.

A USEFUL STARTING POINT

Make a small change deliberately

Changing a view and replacing a byte are different operations. Keep the original in reach with Undo and check the current buffer before creating a file.

FROM QUESTION TO EVIDENCE

Three steps to a useful result.

  1. 01

    Load

    Apply the original bytes.

  2. 02

    Edit or undo

    Change one selected byte and check the result.

  3. 03

    Keep

    Download the complete current buffer explicitly.

A CONCRETE EXAMPLE

Change A to B, then restore it

In the sequence 41 C3 A9 0D 0A, replacing the first byte with 42 changes A to B in UTF-8. Undo restores 41. The checked download contains the restored original five bytes.

WHEN CHECKS REPEAT

From a useful check to everyday work.

These SmartFACT services handle work that repeats across a team or on each job. The workbench remains free and independent.

Early access

SmartFACT Data

When reviewed reference values need to be maintained by a team, SmartFACT Data, including ConfigSheets, provides maintained tables and agreed receiving workflows. It is in early access.

Explore SmartFACT Data ↗Request early access ↗
Invited trial

LabelRules

When label requirements must be checked on every job, LabelRules turns requirements described in plain English into reviewed rules for label selection and value checks. It starts with an invited trial.

Explore LabelRules ↗Request a trial ↗

BEFORE YOU START

A few practical answers.

How far can I undo?

Up to 20 byte-change undo steps.

Does downloading overwrite my original file?

No. It creates a new local file.

Does the grid show every byte at once?

It previews 256 bytes. Complete counts and exports remain available.

Can I edit a disk or unlimited file?

No. This is a browser-local buffer limited to 64 KiB.

What are the current limits?

The buffer is limited to 65,536 bytes (64 KiB), with 20 byte-change undo steps. Byte-grid preview shows 256 bytes, character inspection 128 code points and comparison 100 differing positions; counts and exports use the full buffer. Supported encodings are explicit; invalid text is reported, never repaired. Browser text entry may normalise line endings, so use hex or a local file for exact original bytes. This is a small byte workbench, not a disk editor or file-format parser.

What happens to my data?

Your input, byte buffer, comparison and undo history stay in this tab’s memory. Files are read only when you choose one, never uploaded, and file names are not kept. Refreshing or closing the tab discards this work. Clipboard copies and downloaded files can outlive the tab. The tool has no analytics or automatic storage. These public pages offer the suite’s optional analytics separately; ordinary requests for pages, scripts and the same-origin suite catalogue may be logged by hosting providers.

ONE SMALL JOB, DONE WELL

Put OctetBench to work.

Open the free tool and start with one known example.

Edit bytes locally →

MORE WAYS TO USE OCTETBENCH

Start with the problem in front of you.

Hidden characters Base64 to text Compare hex bytes

THE SMARTFACT SUITE

Practical tools. Useful on their own.
Better around the same floor.

Automate factory decisions with rules you describe in plain English. Explore focused SmartFACT services, plus free tools for everyday checks.

Early accessSuggested next step

SmartFACT Data

Maintain reference tables with ConfigSheets or bring shop orders into SmartFACT through reviewed connectors. Check changes and deliver data to the products that use it.

Explore SmartFACT Data ↗
Invited trial

LabelRules

Describe label rules in plain English. Automatically select layouts, resolve customer codes and check each job before printing.

Explore LabelRules ↗
Early access

KitProof

Turn plain English component rules into automatic kit checklists, then check scans against the expected parts and quantities.

Explore KitProof ↗
Early access

WorkSteps

Turn plain English rules into automatic step selection for each unit, with required evidence and a record of completed work.

Explore WorkSteps ↗
Early access

FactorySpec

Apply approved product rules and calculations automatically to turn dimensions and options into manufacturing requirements.

Register early-access interest ↗
Early access

ParcelOffice

Scan the work order and the parcel choice to book the courier and print the labels. Approved plain English rules recommend or choose the parcel.

Explore ParcelOffice ↗
Early access

RefillFlow

Scan an empty container to send the right refill request to stores. Approved plain English rules set the stores queue, priority, ticket printer and escalation.

Explore RefillFlow ↗
Early access

RemnantRack

Label each offcut, find a suitable length before cutting new stock and record what you used. Approved plain English rules decide what to keep and where it goes.

Explore RemnantRack ↗
Invited trial

ToolCustody

Check a shared tool before handover, record who has it and keep damaged or overdue tools out of the next issue. Explore an invited trial for one factory crib.

Explore ToolCustody ↗
Invited trial

StoresFlow

Receive, put away, reserve and issue stores material with barcode checks, keeping held, reserved and available stock apart. Explore an invited trial for one stockroom.

Explore StoresFlow ↗
Invited trial

LotTrail

Follow a lot or serial number through the records your factory already keeps, with the source of each link and the gaps shown. Explore an invited trial with two declared sources.

Explore LotTrail ↗
Early access

CheckStation

Scan an identified unit to get its approved final-inspection checks, then record exact readings with their result, holds and release history.

Register early-access interest ↗
Invited trial

ReclaimStation

Book returned units in, recover and label the usable parts, release them independently and record the unit each goes into. Explore an invited trial for one product family.

Explore ReclaimStation ↗
Free tool

ScannerBench

See the text and key events your keyboard scanner sends. Compare them with the value you expected.

Test a scanner ↗
Free tool

PrintBench

Print a known PDF, measure its reference marks and compare scans from the printed codes.

Check a print ↗
Free tool

CardBench

Create 100 × 50 mm bin and rack cards with Code 128 or QR, from one record or a CSV.

Make bin cards ↗
Free tool

CountBench

Count stock by location with a barcode scanner, compare it with a stock file and export the results. No account needed.

Start a free count ↗
Free tool

BarcodeBench

See exactly what a scanned barcode contains, with hidden characters shown and GS1 fields, check digits and dates explained. No account needed.

Inspect a barcode ↗
Free tool

MatchBench

Scan a reference and each label, see an exact match or the first difference, and download the results. No account needed.

Start a free comparison ↗
Free tool

TagBench

Scan an item or location, note what needs attention, print a review tag and keep a review list. No account needed.

Make a free tag ↗
Free tool

FindBench

Load your own parts and locations CSV, scan a code and see every location it lists. No account needed.

Start a free lookup ↗
Free tool

ManifestBench

Check cartons, pallets or serial numbers against a list with a phone or scanner and see what is missing. No account needed.

Start a free check ↗
Free tool

FeedBench

Check CSV and JSON files exactly as written, preview a column mapping and compare two versions by key. No account needed.

Check a file free ↗
Free tool

CycleBench

Time work cycles and changeovers on a phone, record interruptions with reasons and download the results. No account needed.

Start a free study ↗
Free tool

OffcutBench

Label the offcuts on your rack, find a piece long enough before cutting new stock and record what you used. No account needed.

Track offcuts free ↗
Free tool

TraceBench

Load one or two CSV exports and follow a lot or serial forwards or backwards, with the row behind every link. No account needed.

Start a free trace ↗
Free tool

ReclaimBench

Record the parts recovered from each return, label them with a QR code, check them and record the unit each one goes into. No account needed.

Track recovered parts free ↗
Free tool

GuidBench

Generate GUIDs, UUID v4 and v7, ULIDs and Nano IDs, format and download batches, or inspect a UUID in your browser. No account needed.

Generate identifiers ↗
Free tool

OctetBench

Inspect and edit text, hex, Base64 and binary bytes in your browser, reveal hidden characters and compare byte sequences. No account needed.

You are here
Free tool

PatternBench

Test JavaScript regular expressions in your browser, inspect matches and captures, preview replacements and check expected cases. No account needed.

Test a pattern ↗
Help

SmartFACT Help

Step-by-step guides and interactive demonstrations for the SmartFACT suite. Read the instructions, watch a task or practise with real product screens and sample data.

Open SmartFACT Help ↗