Messaging · MMS
MMS size limit checker.
Pick your media files and enter the message text. The tool adds up the combined size against the 5 MB limit and checks each file name.
What is the MMS size limit?
Twilio documents that for an outbound message the combined size of the message and its media must stay below the channel maximum, and that the MMS maximum is 5 MB (RCS is 16 MB). Twilio returns an error if any single file, or the collection of files, goes over. This tool adds the byte size of every file you choose to the UTF-8 size of the message text and compares the total to that limit.
File names. Twilio also requires media file names to be 20 characters or fewer and to use only ASCII letters, numbers, hyphens, underscores and periods. A name such as café menu.png fails (an accent and a space), and so does any name over 20 characters including the extension.
Worked example. A 4.9 MB photo (4,900,000 bytes) plus a 200-byte message is 4,900,200 bytes, under 5,000,000. A 5.1 MB video is over the limit on its own and needs compressing.
Carriers differ. Twilio notes that carrier-specific size limits for non-image files exist and are documented elsewhere. Passing this check means you are within Twilio’s published rule, not that every carrier will deliver every file at that size; many people compress images well below the limit.
Frequently asked questions
What is the maximum MMS size?
Twilio documents 5 MB for MMS, counted as the combined size of the message and its media. RCS is 16 MB.
Does the message text count toward the MMS limit?
Yes. Twilio says the combined size of the message and its media must stay below the channel maximum, so this tool adds the text bytes to the file sizes.
What are the MMS file name rules?
Twilio requires file names of 20 characters or fewer, using only ASCII letters, numbers, hyphens, underscores and periods.
Is 5 MB 5,000,000 or 5,242,880 bytes?
Twilio does not say. The checker marks anything under 5,000,000 bytes as safe, anything above 5,242,880 as over, and the range between them as borderline.
Are my files uploaded?
No. The browser reads each file’s name and size only; the contents are never read or sent.
Sources
Checked
Twilio gives the 5 MB MMS limit, the combined-size rule, the 20-character file name limit and the allowed characters. It does not define MB, so the checker shows a borderline band. Carrier-specific limits for non-image files are not modelled. Files are not uploaded.
Scope
The limit applies to Twilio’s Programmable Messaging; other providers and carriers may set different limits. Test a real send for important campaigns.