Last updated: 2026-08-02

Microsoft (Bing) Ads Character Limits - Headlines, Descriptions, and Paths

Microsoft Advertising (formerly Bing Ads) caps responsive search ad headlines at 30 characters, descriptions at 90 characters, and each display path at 15 characters - and for languages with double-width characters such as Japanese, Chinese, and Korean, every one of those limits is halved. The numbers below come from Microsoft's official Campaign Management API reference (the ResponsiveSearchAd specification), current as of 2026. This article covers each limit in detail, the double-width rule that catches multilingual advertisers, and what actually differs from Google Ads when you import campaigns.

Microsoft Advertising Character Limits at a Glance

Responsive search ads (RSA) are the standard search ad format in Microsoft Advertising, just as they are in Google Ads. You supply between 3 and 15 headlines and 2 to 4 descriptions, and the ad platform assembles the combination it predicts will perform best for each query - showing up to 3 headlines and 2 descriptions at a time. If a specific message must always appear, you can pin an asset to a fixed position, at the cost of reducing the combinations the system can test.

The Double-Width Rule: Japanese, Chinese, Korean, and Emoji Count Double

Microsoft's documentation is unusually explicit about how non-Latin text is measured: for "languages with double-width characters," the effective limits are half the standard ones - 15-character headlines, 45-character descriptions, 7-character paths, and a 33-character display URL budget. Double-width characters include Japanese, Chinese, and Korean characters, and also emoji.

A detail worth noting from the specification: whether the halved limit applies is determined by the characters you actually use, not by the language setting of your campaign or ad group. An English-language campaign that drops a single emoji into a headline is measured against the double-width math for that emoji. In practice, treat each double-width character as costing 2 of the 30/90/15 budget - a headline of 14 Japanese characters plus one ASCII exclamation mark fits, while 15 Japanese characters plus anything does not. Since Japanese copy is often drafted in a document first, run it through a character counter that distinguishes full-width from half-width characters before pasting it into the ad editor.

Display URL: Domain Plus Paths Cannot Exceed 67 Characters

The display URL shown under your ad is assembled from the domain of your final URL plus the optional Path 1 and Path 2 strings. Each path allows up to 15 final characters, but there is a combined ceiling: domain + paths must not exceed 67 characters (33 with double-width characters). A long domain therefore eats directly into your path budget - with a 45-character domain, you have only 22 characters left across both paths, minus separators.

Paths also have formatting constraints from the specification: they cannot contain a forward slash or a newline character, and any space you type is displayed as an underscore. Path 2 can only be set if Path 1 exists. Because the paths are purely cosmetic (the landing page is always the final URL), the practical advice is to spend them on keywords that reinforce the searcher's intent - "/tokyo/pricing" style - rather than replicating your real URL structure.

Dynamic Text: 1,000 Characters In, 30 or 90 Out

Headlines, descriptions, and paths can contain dynamic text strings such as {keyword} substitution and IF functions. For these, Microsoft allows a generous input length - up to 1,000 characters of raw text including the dynamic syntax - but the text that results after substitution must still fit the final limits: 30 characters for a headline, 90 for a description, 15 per path. The double-width rule applies to the input budget as well: for headlines and descriptions written in double-width languages, the maximum input length drops to 500 characters (paths keep the 1,000-character input allowance). If a substituted value pushes the text over the limit, the ad fails to display or falls back to the default text you defined. The safe pattern is to write default text near the limit and keep inserted keywords short, then spot-check your longest keywords against the 30-character ceiling.

Microsoft Ads vs. Google Ads: Same Numbers, Different Fine Print

Because the headline, description, and path numbers match, importing Google campaigns into Microsoft Advertising usually carries ad copy over without truncation - this is deliberate, and it is why many advertisers manage Bing as a low-maintenance mirror of their Google account. The fine print differs in two places: Microsoft publishes an explicit combined display-URL cap (67/33), and its double-width rule is defined per character used rather than per campaign language. Copy written to the exact 30/90 ceiling in English can still overflow after localization, for the information-density reasons covered in our ad copy character limits guide. For the Google side of the comparison, see Google Ads character limits.

Practical Lengths: The Limit Is Not the Target

As with every ad platform, filling the entire budget is not the goal. Headlines in the 20 to 26 character range avoid mid-word truncation across device layouts and stay scannable; descriptions of 70 to 85 characters fit within two lines on mobile. Front-load the benefit into the first two or three words - eye-tracking studies of search results consistently show later words in a headline receive only glancing attention. And register enough assets for the system to work with: the 3-headline minimum produces exactly one possible ad, leaving the optimizer nothing to test.

Bottom Line

Memorize three numbers for Microsoft (Bing) Ads: 30, 90, and 15 - headline, description, path. Halve all of them the moment your copy contains Japanese, Chinese, Korean, or emoji, and keep domain plus paths under 67 characters. Verify your drafts with the character counter (the full-width/half-width breakdown maps directly onto Microsoft's double-width rule) before submitting, and your ads will clear editorial review without length surprises. For broader copywriting technique, there are copywriting books on Amazon.