Coupon Code Generator

How do I generate bulk unique coupon codes for free?

Open AnyTool’s Coupon Code Generator, pick a simple length-and-charset or a format pattern like SAVE-####-XXXX, set how many codes you need, and click Generate. You get guaranteed-unique codes you can copy or download as TXT or CSV — all created in your browser, nothing uploaded.

Two modes: simple length + character set, or a pattern (# digit, X letter, ? alphanumeric, * your charset)
Add a prefix, suffix, segment separators, and exclude look-alike characters (O/0/I/1)
Every code is guaranteed unique within the batch — up to 10,000 at once
Optional checksum character catches most mistyped codes
Copy all or download as .txt / .csv — 100% client-side, no signup

What is

A coupon code generator creates batches of unique promo, voucher or discount codes from a chosen length and character set or a format pattern. The codes are random strings for use in a store; the actual discount, expiry and redemption limits are configured separately in your e-commerce system.

Marketing Tools

Related terms

Promo CodeVoucher CodeDiscount CodePatternChecksum

Frequently Asked Questions

Open AnyTool’s Coupon Code Generator and pick simple mode (a length plus a character set) or pattern mode (a template such as SUMMER-####-2026, where # is a digit, X a letter, ? alphanumeric and * your own charset). Add an optional prefix, suffix or separators, set how many codes you need — up to 10,000 — and click Generate. Every code in the batch is deduplicated so they are all unique, and you can copy them all or download a .txt or .csv. Generation runs entirely in your browser using crypto-secure randomness.

Choose a length or a pattern, set the count, and click Generate. AnyTool produces guaranteed-unique codes you can download as CSV.

Pattern mode lets you fix the exact shape of every code: # fills a digit, X (or A) a letter, ? a letter or digit, * a character from your chosen set, and any other character — letters, hyphens, a year — is kept literally. So WELCOME10-### or GIFT-XXXX-#### come out exactly as written with only the placeholders randomised. In simple mode you set a length, a character set, an optional prefix and suffix, and a segment length plus separator to group the body, for example SAVE-7F3K-9QH2.

Yes — use pattern mode (e.g. SAVE-####-XXXX) or add a prefix/suffix and segment separators in simple mode.

The generator only creates the code strings — it does not connect to any shop, so it cannot apply a discount, set an expiry, or limit redemptions on its own. Generate the list, download the CSV, and import it into Shopify, WooCommerce, Stripe, Magento or your own system, where you configure the discount value, the redemption limit (such as one-per-customer) and the expiry date. If you run several campaigns, de-duplicate new batches against codes you have already issued before going live.

They are random unique strings. You import them into your store and set the real discount, expiry and usage limit there.

AnyTool’s Coupon Code Generator is free with no account or limits beyond a 10,000-per-batch cap. All codes are generated locally with the Web Crypto API, so nothing — not your codes, prefixes, or CSV annotations — is ever sent to a server, logged or stored. It works offline once the page is cached, which makes it safe for internal campaign codes.

Yes — it is completely free, needs no signup, and every code is generated in your browser without uploading anything.

Detailed Explanation

Methodology

How the Coupon Code Generator Builds Codes

AnyTool Coupon Code Generator creates promo, voucher and discount codes entirely in the browser using the Web Crypto API (secureRandomInt with rejection sampling, so character choice is uniform and free of modulo bias — never Math.random). It offers two modes. Simple mode takes a length and a character set (letters+digits, letters only, or digits only, or a custom set) and can split the body into fixed-length segments joined by a separator, for example SAVE-7F3K-9QH2. Pattern mode takes a template in which # is replaced by a digit, X or A by a letter, ? by a letter or digit, and * by your chosen character set, while every other character is copied literally — so SUMMER-####-2026 or GIFT-XXXX-#### keep their fixed text and randomise only the placeholders.

Randomness from crypto.getRandomValues via secureRandomInt — no modulo bias
Simple mode: length + character set, optional segment grouping
Pattern mode: # digit, X/A letter, ? alphanumeric, * custom set, others literal
Optional prefix, suffix, exclude look-alikes (O/0/I/1) and force-uppercase
All generation is client-side JavaScript — no server round-trip

How It Works

Guaranteed Uniqueness, Capacity and Checksums

Every batch is deduplicated as it is built, so all codes returned are unique within that batch — up to a cap of 10,000 per generate. The engine computes the keyspace (the number of distinct random codes the settings allow) and, if a request exceeds it, transparently produces as many unique codes as possible and reports the limit rather than looping forever. An optional checksum character — a deterministic weighted mod-37 value emitted in base 36 — can be appended so that most single-character typos and many transpositions in a hand-keyed code are detectable before checkout. Output can be copied or downloaded as a plain .txt list or an RFC-4180 CSV that optionally carries constant discount and expiry columns to ease importing.

Codes are deduplicated — guaranteed unique within each batch
Up to 10,000 codes per batch; keyspace is computed to avoid impossible requests
Optional weighted mod-37 checksum character for typo detection
Export as plain .txt or RFC-4180 CSV with optional discount/expiry columns
Pattern impossibility and over-capacity counts are handled gracefully

Privacy & Security

Scope, Store Integration and Privacy

The tool generates code strings only; it does not connect to any store, so it cannot set a discount amount, an expiry date, or a per-customer usage limit, and it cannot prevent a code being reused. Those rules are configured where the codes are imported — Shopify, WooCommerce, Stripe, Magento or a custom system — and when multiple batches are issued over time they should be de-duplicated against previously issued codes before going live. Because all generation happens in the browser, no code, prefix, or CSV annotation is ever uploaded, logged or stored; the page works offline once cached, which suits internal or pre-launch campaign codes.

Creates code strings only — discount, expiry and limits live in your store
Uniqueness is within a single batch; de-duplicate across batches yourself
Nothing is uploaded, logged or stored — works offline once cached
Suitable for Shopify, WooCommerce, Stripe, Magento and custom imports

Coupon code generation: in-browser (AnyTool) vs typical online generators
Capability	AnyTool	Typical online generators
Processing	Runs entirely in your browser	Often server-side
Randomness	Web Crypto CSPRNG, rejection sampling	Sometimes Math.random / server-side
Format control	Pattern (#/X/?/*) + prefix/suffix/segments	Often prefix + length only
Uniqueness	Guaranteed unique within the batch	Usually, but not always stated
Batch size	Up to 10,000 per generate	Often capped, then gated
Typo protection	Optional checksum character	Rare
Export	Copy-all, .txt and CSV (discount/expiry cols)	CSV common; options vary
Privacy	Never uploaded, works offline	May transmit or log your codes
Cost / signup	Free, no signup	Often ad-heavy or gated

AnyTool generates every code locally with crypto-secure randomness and uploads nothing. The discount, expiry and redemption limits are enforced in your own store.

Cite This Page

Title: Coupon Code Generator (bulk unique promo, voucher & discount codes with custom patterns and CSV export, 100% client-side)
Author: AnyTool
Published: January 1, 2026
Modified: February 8, 2026
Section: Generators
URL: https://www.anytool.tech/coupon-code-generator

Formatted Citation

AnyTool. "Coupon Code Generator (bulk unique promo, voucher & discount codes with custom patterns and CSV export, 100% client-side)." AnyTool, January 1, 2026. https://www.anytool.tech/coupon-code-generator

A privacy-first, 100% client-side coupon, promo and voucher code generator that builds codes in the browser from a small pure engine reusing the Web Crypto API (secureRandomInt with rejection sampling, so character choice is uniform and free of modulo bias and Math.random is never used for code material). It offers two modes: a simple mode that takes a length and a character set (letters+digits, letters only, digits only, or a custom set) and can group the body into fixed-length segments joined by a separator such as SAVE-7F3K-9QH2; and a pattern mode whose template fills # with a digit, X or A with a letter, ? with a letter or digit and * with the chosen set while copying every other character literally, so SUMMER-####-2026 or GIFT-XXXX-#### preserve their fixed text. Codes can carry a prefix and suffix, be forced uppercase, exclude visually-ambiguous characters (O, 0, I, 1), and optionally append a single deterministic weighted mod-37 checksum character emitted in base 36 so most hand-keying typos and transpositions are detectable. Every batch is deduplicated for guaranteed in-batch uniqueness up to a cap of 10,000 codes, with the keyspace computed so that an over-capacity request returns as many unique codes as possible and reports the limit rather than looping forever; results are shown in a scrollable list and exported by copy-all or as a plain .txt list or an RFC-4180 CSV that can include constant discount and expiry columns for easy importing. The page is explicit that the tool produces random code strings only and does not connect to any store, so the real discount value, expiry date and per-customer redemption limit must be configured where the codes are imported — Shopify, WooCommerce, Stripe, Magento or a custom system — and that batches issued over time should be de-duplicated against previously issued codes; nothing is uploaded, logged or stored and the tool works offline once cached.