{"id":25038,"date":"2025-12-04T09:51:21","date_gmt":"2025-12-04T09:51:21","guid":{"rendered":"https:\/\/www.yousanusb.com\/?p=25038"},"modified":"2026-01-07T10:55:07","modified_gmt":"2026-01-07T10:55:07","slug":"how-to-test-the-actual-capacity-of-a-usb-flash-drive-using-free-software","status":"publish","type":"post","link":"https:\/\/www.yousanusb.com\/es\/how-to-test-the-actual-capacity-of-a-usb-flash-drive-using-free-software\/","title":{"rendered":"\u00bfC\u00f3mo comprobar la capacidad real de una memoria USB con software gratuito?"},"content":{"rendered":"

So why do some 64GB USB Flash Drives cost 25 yuan while others are only 15? Beware – you could well be buying a \u2018capacity expanded drive\u2019. I\u2019m Mona, from Shenzhen YOUSAN USB flash drive Factory and I\u2019m going to burn my bridges and expose the biggest dark secret in the industry. Let\u2019s use the free, and pretty neat software \u2018H2testw\u2019 to find out.<\/p>\n\n\n\n

1. What is an \u201cexpansion drive\u201d?<\/h2>\n\n\n\n

What you thought was \u201cfake goods\u201d: Rough casing, no response when you plug it in. No, today\u2019s \u201ccapacity-expanded drives\u201d are smarter than that. They are smarter than you think. When you hook a USB drive sold as 64GB into your computer Windows will report: \u201cAvailable space: 62.5GB\u201d. You can even drop files onto it and the progress bar looks normal! Everything looks perfect. The black tech behind it: Small workshops or rogue manufacturers recycle found 4GB chips. They adjust some controller parameters using mass-production machinery, fooling the whole computer system into displaying as a 64GB device. It\u2019s like a bucket that only holds 4 litres of water getting a sticker slapped on it saying \u201c64 litres\u201d and selling it to you at 64 litres price.<\/p>\n\n\n\n

2. What Happens When Using Expansion Drives?<\/h2>\n\n\n\n

Many buyers opt for these drives to save money, only to get severely reprimanded by their bosses. Expansion drives have a critical flaw: Loop Write.<\/p>\n\n\n\n

    \n
  1. 1st 4Gb : normal writes, files open. <\/li>\n\n\n\n
  2. 4Gb or more : \u201cWrite successful\u201d is displayed and the datd is written to disk – but since no physical space is left, the new data overwrites the old, or just disappears. <\/li>\n\n\n\n
  3. Your customer gets the USB stick, copies all their photos and contracts, and opens it up when they get home. And the filenames are all there, but the contents of the files is gibberish or fails to open, all the data is completely out of action.<\/li>\n<\/ol>\n\n\n\n

    3. How to test the actual capacity using H2testw?<\/h2>\n\n\n\n

    When faced with this situation, don\u2019t take the vendor\u2019s word for it, and don\u2019t trust what your computer tells you about its properties. The truth will become apparent with just one free piece of software: H2testw. It\u2019s the world standard for determining true capacity in the industry. <\/p>\n\n\n\n

    Step-By-Step process (Mona\u2019s Step-By-Step Walkthrough):<\/p>\n\n\n\n

    \n
    \n
    \"\"<\/figure>\n<\/div>\n\n\n\n
    \n
      \n
    1. Download: If that wasn\u2019t obvious enough, just Google search \u201cH2testw download\u201d. It\u2019s free and requires no installation! <\/li>\n\n\n\n
    2. Download and unzip\/program files: Go to H2testw\u2019s official site http:\/\/h2testw.de and download the latest version evidenced at the top of the page. You should have a file named \u201ch2testw_1.4.zip\u201d. First, unzip the file and read through the instructions. <\/li>\n\n\n\n
    3. Setup: Insert your USB drive, open H2testw, select English (English interface), and select your USB drive under Target. Test: Select \u201cWrite + Verify\u201d. Fills the drive with data and then reads it back to see if it actually is that full.<\/li>\n<\/ol>\n<\/div>\n<\/div>\n\n\n\n
      \n
      \n

      <\/p>\n\n\n\n

      View Results (Truth Revealed):<\/strong>
      All Green<\/strong> (Test passed without errors): Congratulations! This is truly a real full-speed storage device.
      Turns Red<\/strong> (Data Lost \/ Corrupted):
      ALERT! This is an over-provisioned storage device.
      The red bar shows<\/strong>: Actual storage capacity is only X GB, and the other is fake.
      The H2testw program is free software that requires no installation and is used for storage media tests: checks for actual capacity of USB drives\/SD cards; analyzes bad sectors; analyzes read and write transfer rates.<\/p>\n<\/div>\n\n\n\n

      \n
      \"\"<\/figure>\n<\/div>\n<\/div>\n\n\n\n

      4. YOUSAN Professional USB Drive Manufacturer’s Commitment:We Sell Reputation, Not Trash!<\/h2>\n\n\n\n

      In Shenzhen’s electronics wholesale markets, overcapacity drives can double profits, but YOUSAN usb flash drive steadfastly refuses to manufacture them.
      Every chip we use is Grade A genuine full-capacity, such as from Samsung\/SK Hynix\/Micron, etc. Before shipment, 100% of our QC assembly line conducts H2testw verification. We do not have to “steal capacity” in order to make money, which means we want to see your repeat orders next year!<\/p>\n\n\n\n

      Mona’s Advice<\/strong>:
      No matter who you buy USB Flash drives from, send this message to your supplier before placing an order:
      \u201cAcceptance based on H2testw results. If it fails (Red bar), I will return all units and refuse payment.\u201d
      If they respond evasively, it shows they have something to hide and won’t dare take your order. If they’re an honest factory like YOUSAN, they’ll applaud you.<\/p>","protected":false},"excerpt":{"rendered":"

      So why do some 64GB USB Flash Drives cost 25 yuan while others are only 15? Beware – you could well be buying a \u2018capacity expanded drive\u2019. I\u2019m Mona, from Shenzhen YOUSAN USB flash drive Factory and I\u2019m going to burn my bridges and expose the biggest dark secret in the industry. Let\u2019s use the …<\/p>\n

      \u00bfC\u00f3mo comprobar la capacidad real de una memoria USB con software gratuito?<\/span> Leer m\u00e1s »<\/a><\/p>","protected":false},"author":1,"featured_media":25123,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"none","_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","footnotes":""},"categories":[140],"tags":[],"class_list":["post-25038","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-usb-flash-drive-knowledge"],"_links":{"self":[{"href":"https:\/\/www.yousanusb.com\/es\/wp-json\/wp\/v2\/posts\/25038"}],"collection":[{"href":"https:\/\/www.yousanusb.com\/es\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.yousanusb.com\/es\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.yousanusb.com\/es\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.yousanusb.com\/es\/wp-json\/wp\/v2\/comments?post=25038"}],"version-history":[{"count":15,"href":"https:\/\/www.yousanusb.com\/es\/wp-json\/wp\/v2\/posts\/25038\/revisions"}],"predecessor-version":[{"id":26928,"href":"https:\/\/www.yousanusb.com\/es\/wp-json\/wp\/v2\/posts\/25038\/revisions\/26928"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.yousanusb.com\/es\/wp-json\/wp\/v2\/media\/25123"}],"wp:attachment":[{"href":"https:\/\/www.yousanusb.com\/es\/wp-json\/wp\/v2\/media?parent=25038"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.yousanusb.com\/es\/wp-json\/wp\/v2\/categories?post=25038"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.yousanusb.com\/es\/wp-json\/wp\/v2\/tags?post=25038"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}