Free Amazon byte toolfree tool

Count Amazon keyword bytes before the field breaks.

Paste a backend keyword field or keyword list. The tool returns byte count, duplicate terms, over-limit warning, unsupported-term warning, cleaned keyword preview, and a Central handoff for marketplace copy from verified product facts.

byte countduplicate detectionunsupported terms flaggedCentral workflow bridge

Input 1 field / session

Keyword field required Counts bytes — not characters — so accents and non-ASCII characters are measured correctly.

Product facts optional · verified terms to preserve

Terms to exclude optional

Byte target custom Locale

Try example Clear

Result · keyword field audit over budget

268/ 250 bytes

over by 18

250target 268used 18over · 7% en-USascii + 6 non-ascii bytes

Findings3 issues · 1 cleaned

Duplicate terms · 2

steel ×2compact ×2

Repeated within the field. Dropping duplicates frees 13 bytes.

Needs source · 1

waterproof

Not present in the provided product facts. Marked Needs source — keep out of the field until evidence supports it.

Excluded · 1 brand-restricted term filtered

yeti

Filtered by your exclusion list.

Cleaned field · 247 / 250 byteswithin budget

compact tumbler insulated steel travel mug stainless double walled vacuum bottle leakproof hydration café reusable to go

→ continue in Central

why this matters

Keyword fields fail quietly when bytes are wrong.

Amazon-style keyword work is not only about adding more terms. Byte limits, duplicate words, accented characters, and unsupported claims can make the field weaker or unsafe.

✓ what the tool can do

Byte counting and cleanup for one field.

Count bytes — total, remaining, and over-limit warning against your target.
Flag duplicate terms — exact matches and near-duplicates highlighted.
Mark unsupported terms — anything not present in your product facts gets Needs source.
Output a cleaned field — deduplicated, filtered, ready to paste.

where Central adds proof

Verify keyword truth from the product record.

Source discovery for claims beyond the facts you paste.
Configurable marketplace limits so exact byte targets stay current.
Product-fact keyword suggestions without competitor or brand-stuffing risk.
Batch workflow for catalog runs inside Central.

from utility to verified workflow

Count bytes once. Build listing output from the record.

Inside Central, marketplace keyword and title work can run from the verified product record — with source trails, confidence, and review states before terms are used in listing output.

byte counter · this page

One field

Byte count, duplicates, unsupported terms, cleaned preview. Useful once, for one keyword field.

→

central · verification

Terms + claims verified

Every keyword and bullet grounded in the verified product record. Confidence per fact. Held claims stay out.

→

marketplace output

Title + bullets + keywords

Marketplace copy generated from the canonical record. Review states visible before export.

Build listing from verified facts See all free tools ↗

FAQ

Four questions about the byte counter.

Why count bytes instead of characters?

Some marketplace fields are byte constrained. Accents, symbols, and non-ASCII characters can use more bytes than plain ASCII — a 250-character field can easily exceed a 250-byte limit when "café", "wasserdicht" or em-dashes appear.

Does the tool know Amazon's current policy?

Keep exact limits and policy guidance implementation-driven. The tool allows a custom target and avoids stale public promises — set your byte target to whatever your category and account currently support.

Will it suggest competitor keywords?

No. The tool focuses on product facts and warnings, not risky keyword stuffing. Brand-restricted and competitor terms can be added to the exclusion list and are filtered out of the cleaned field.

Can Central run this across many SKUs?

Yes. Central can connect marketplace listing work to verified records and batch workflows — the same byte audit, term verification, and cleaned-output pattern applied to every SKU, with source trails and review states attached.